comparative study of three methods of calculating atomic charge in a molecule

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Comparative Study of Three Comparative Study of Three Methods of Calculating Atomic Methods of Calculating Atomic Charge in a Molecule Charge in a Molecule Wanda Lew Wanda Lew Heather Heather Harding Harding Sharam Emami Sharam Emami Shungo Miyabe Shungo Miyabe San Francisco State University San Francisco State University Tomekia Simeon Tomekia Simeon Jackson State University Jackson State University Source of Wisdom: Sergio Aragon Source of Wisdom: Sergio Aragon January 16, 2004 January 16, 2004

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Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule. Wanda Lew Heather Harding Sharam Emami Shungo Miyabe San Francisco State University Tomekia Simeon Jackson State University Source of Wisdom: Sergio Aragon January 16, 2004. - PowerPoint PPT Presentation

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Page 1: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Comparative Study of Three Methods of Comparative Study of Three Methods of Calculating Atomic Charge in a MoleculeCalculating Atomic Charge in a Molecule

Wanda Lew Wanda Lew Heather Heather Harding Harding

Sharam Emami Sharam Emami Shungo MiyabeShungo MiyabeSan Francisco State UniversitySan Francisco State University

Tomekia SimeonTomekia SimeonJackson State UniversityJackson State University

Source of Wisdom: Sergio AragonSource of Wisdom: Sergio Aragon

January 16, 2004January 16, 2004

Page 2: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Why is assigning charges to various atoms Why is assigning charges to various atoms of a molecule of interest?of a molecule of interest?

Assigning charge to various atoms allowsAssigning charge to various atoms allows::

• Prediction of reactive sites in a moleculePrediction of reactive sites in a molecule

• Charge distribution determines all Charge distribution determines all molecular propertiesmolecular properties

Andrew S. IchimuraSFSU presentation 9/26/03

Page 3: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Why isn’t there just one best method that everyone Why isn’t there just one best method that everyone uses to calculate atomic charge?uses to calculate atomic charge?• No concensus on what criteria to use to judge No concensus on what criteria to use to judge

which method is better i.e. which method is better i.e.

a.a. Do we arbitrarily say that if a method is Do we arbitrarily say that if a method is basis set independentbasis set independent it is “better”?* it is “better”?*

b.b. Or is the better method one that’s Or is the better method one that’s able to able to account for anticipated changes in account for anticipated changes in charge distribution after various charge distribution after various perturbations to the moleculeperturbations to the molecule such as: such as:

● ● varying dihedral angles* in a varying dihedral angles* in a moleculemolecule

Page 4: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

We Decided to Examine Three Methods We Decided to Examine Three Methods for Assigning Charges to Atoms in a for Assigning Charges to Atoms in a

MoleculeMolecule

• Population Analysis (R.S. Mulliken, 1955)Population Analysis (R.S. Mulliken, 1955)

• Atoms in Molecule (R.W.F. Bader, 1965)Atoms in Molecule (R.W.F. Bader, 1965)

• Electrostatic Potential (Merz-Sing-Kollman)Electrostatic Potential (Merz-Sing-Kollman)

Page 5: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

What is Population Analysis?What is Population Analysis?• This method was proposed by R.S. Mulliken This method was proposed by R.S. Mulliken

Sample Molecule:Sample Molecule: A-B A-B

• To assign charge on atom A, uses a molecular To assign charge on atom A, uses a molecular orbital function represented by a linear orbital function represented by a linear combination of the atomic orbitalscombination of the atomic orbitals

=C=CAAAA + C + CBBB B =N(C=N(CA A 22 + + 2C2CAACCBBSSABAB+ C+ CB B

22 ))

Mulliken Charge on Atom A would be:Mulliken Charge on Atom A would be: Q QAA=N(C=N(CAA

22 + + CCAACCBBSSABAB))• Weaknesses:Weaknesses:

a.a. Divides overlap term symmetricallyDivides overlap term symmetrically

b.b. Atomic orbital term Atomic orbital term CCAA2 2 assigned to atom even if assigned to atom even if

the charge on that atom is polarized/diffuse the charge on that atom is polarized/diffuse enough to bleed some e- density into neighboring enough to bleed some e- density into neighboring atomatom

Page 6: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Electrostatic PotentialElectrostatic Potential• Ability to compute the degree to which a Ability to compute the degree to which a

positive or negative test charge is attracted positive or negative test charge is attracted to or repelled by the molecule that is being to or repelled by the molecule that is being represented by the multipole expansion.represented by the multipole expansion.

• ESP is directly calculated from the electron ESP is directly calculated from the electron density using a many electron wavefunction density using a many electron wavefunction and point charges of the nuclei.and point charges of the nuclei.

Page 7: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

• Electrostatic potential is both Electrostatic potential is both a molecular property and a a molecular property and a spatial property.spatial property.

• It depends on what charges It depends on what charges exist in the molecule and how exist in the molecule and how they there are distributed.they there are distributed.

• The electrostatic potential The electrostatic potential created by a system of created by a system of charges at a particular point charges at a particular point in space, (in space, (x, y, zx, y, z), is equal to ), is equal to the change in potential the change in potential energy that occurs when a +1 energy that occurs when a +1 ion is introduced at this ion is introduced at this point.point.

It also depends on what point It also depends on what point

• (x, y, z)(x, y, z) we choose to investigate. If we select a point where we choose to investigate. If we select a point where the +1 charge is attracted by the molecule, the potential will be the +1 charge is attracted by the molecule, the potential will be negative at this point. negative at this point.

• On the other hand, if we select a point where the +1 charge is On the other hand, if we select a point where the +1 charge is repelled, the potential will be positive.repelled, the potential will be positive.

Page 8: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

AIM AIM

• Let Let (r) be the electron density (r) be the electron density

• Gradient of Gradient of (r) is a vector that points in the direction of (r) is a vector that points in the direction of maximum increase in the density. One makes an maximum increase in the density. One makes an infinitesimal step in this direction and then recalculates infinitesimal step in this direction and then recalculates the gradient to obtain the new direction. By continued the gradient to obtain the new direction. By continued repetition of this process, one traces out a trajectory of repetition of this process, one traces out a trajectory of (r).(r).

Page 9: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

AIM (cont.)AIM (cont.)

• A gradient vector map generated for ethene:A gradient vector map generated for ethene:

• Since the density exhibits a maximum at the position of Since the density exhibits a maximum at the position of each nucleus, sets of trajectories terminate at each each nucleus, sets of trajectories terminate at each nucleus. The nuclei are the nucleus. The nuclei are the attractorsattractors of the gradient of the gradient vector field of the electron density. vector field of the electron density.

Page 10: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

AIM (cont.)AIM (cont.)

• The molecule is disjointly and exhaustively partitioned into The molecule is disjointly and exhaustively partitioned into basins, a basin being the region of space traversed by the basins, a basin being the region of space traversed by the trajectories terminating at a given nucleus or attractor. trajectories terminating at a given nucleus or attractor.

• An An atomatom is defined as the union of an attractor and its basin is defined as the union of an attractor and its basin

Page 11: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Comparison of 3 Ways to Calculate Charge Comparison of 3 Ways to Calculate Charge on Atom in a Molecule (MUL, AIM, ESP) on Atom in a Molecule (MUL, AIM, ESP) Using 7 Different MoleculesUsing 7 Different Moleculesa.a. Molecules StudiedMolecules Studied: :

Urea, Proprionitrile, 1,2-difluoroethane, Glycine, Urea, Proprionitrile, 1,2-difluoroethane, Glycine, Serine, Propylaldehyde, propane, propanol Serine, Propylaldehyde, propane, propanol

b.b. Calculation Methods Used: Calculation Methods Used: Hartree-Fock (HF) Hartree-Fock (HF) Density Functional (DFT, specifically B3LYP)Density Functional (DFT, specifically B3LYP)

c.c. Criteria used to evaluate quality of methodCriteria used to evaluate quality of method::i. independence of basis set (STO-3g, 321g, 631g, i. independence of basis set (STO-3g, 321g, 631g, 6311g, 6311g*, 6311g**)6311g, 6311g*, 6311g**)ii. How charge on atom changes with change in ii. How charge on atom changes with change in dihedral anglesdihedral angles

Andrew S. IchimuraSFSU presentation 9/26/03

Page 12: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Basis Set Dependence of MUL, AIM and ESP –HF Basis Set Dependence of MUL, AIM and ESP –HF MethodMethod

Urea Mulliken Charge with Hartree-Fock Method at Optimal Geometry

-1.5

-1

-0.5

0

0.5

1

1.5

0 1 2 3 4 5 6 7 8 9

Atom Number

Cha

rge

hfsto3g

hf321g

hf631g

hf6311g

Urea AIM Charge with Hartree-Fock Method at Optimal Geometry

-1.5

-1

-0.5

0

0.5

1

1.5

2

2.5

0 1 2 3 4 5 6 7 8 9

Atom Number

Cha

rge

hfsto3g

hf321g

hf631g

hf6311g

Urea ESP Charge w ith Hartree-Fock Method at Optimal Geometry

-1.5

-1

-0.5

0

0.5

1

1.5

0 1 2 3 4 5 6 7 8 9

Atom Number

Ch

arg

e

hfsto3g

hf321g

hf631g

hf6311g

Urea

1

2

4 38

67

5

Page 13: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Basis Set Dependence MUL, AIM and ESP -- DFT Basis Set Dependence MUL, AIM and ESP -- DFT MethodsMethods

Urea Mulliken Charge with DFT Method at Optimal Geometry

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

0 1 2 3 4 5 6 7 8 9

Atom Number

Cha

rge

blypsto3g

blyp631g

blyp6311g

blyp6311g+

blyp6311g++

blyp6311g++dp

Urea AIM Charge with DFT Method at Optimal Geometry

-1.5

-1

-0.5

0

0.5

1

1.5

2

2.5

0 1 2 3 4 5 6 7 8 9

Atom Number

Cha

rge

blypsto3g

blyp631g

blyp6311g

blyp6311g+

blyp6311g++

blyp6311g++dp

Urea ESP Charge w ith DFT Method at Optimal Geometry

-1.5

-1

-0.5

0

0.5

1

1.5

0 1 2 3 4 5 6 7 8 9

Atom Number

Ch

arg

e

blypsto3g

blyp631g

blyp6311g

blyp6311g+

blyp6311g++

blyp6311g++dp

Urea

1

2

345

6

7

8

Page 14: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Dihedral Angle Dependence of MUL, AIM and ESP Dihedral Angle Dependence of MUL, AIM and ESP with HF Methodswith HF Methods

Urea Mulliken Charge (HF6311g) w ith Varying Dihedral

-1.5

-1

-0.5

0

0.5

1

1.5

0 1 2 3 4 5 6 7 8 9

Atom Number

Ch

arg

e

0

45

90

135

Urea AIM Charge (HF 6311g) with Varied Dihedral Angle

-1.5

-1

-0.5

0

0.5

1

1.5

2

0 1 2 3 4 5 6 7 8 9

Atom Number

0

45

90

135

Urea ESP Charge (HF6311g) with Varied Dihedral Angle

-1.5

-1

-0.5

0

0.5

1

1.5

0 1 2 3 4 5 6 7 8 9

Atom Number

Cha

rge

0

45

90

135

Urea

1

2

348

5

6

7

Page 15: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Dihedral Angle Dependence of MUL, AIM Dihedral Angle Dependence of MUL, AIM and ESP with DFT Methodsand ESP with DFT Methods

Urea ESP Charge (BLYP6311g) with Varied Dihedral Angles

-1.5

-1

-0.5

0

0.5

1

1.5

0 1 2 3 4 5 6 7 8 9

Atom Number

Ch

arg

e

0

45

90

135

Urea AIM Charges (BLYP6311g) with Varied Dihedral Angles

-1.5

-1

-0.5

0

0.5

1

1.5

2

0 1 2 3 4 5 6 7 8 9

Atom Number

Ch

arg

e

0

45

90

135

Urea Mulliken (BLYP6311g) with Varied Dihedral Angles

-1

-0.5

0

0.5

1

0 1 2 3 4 5 6 7 8 9

Atom Number

Cha

rge

0

45

90

135

Page 16: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Basis Set Dependence of MUL, AIM and ESP with Basis Set Dependence of MUL, AIM and ESP with HF MethodsHF Methods

Propionitrile Mulliken Charge via Hartree-Fock Method at Optimal Geometry

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0 2 4 6 8 10

Atom Number

Ch

arg

e

hfsto3g

hf321g

hf631g

hf6311g

Propioniltrile AIM Charge via Hartree-Fock Method at Optimal Geometry

-1.5

-1

-0.5

0

0.5

1

0 1 2 3 4 5 6 7 8 9

Atom Number

Ch

arg

ehfsto3g

hf321g

hf631g

hf6311g

Proprionitrile ESP Charge via Hartree-Fock Method at Optimal Geometry

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0 2 4 6 8 10

Atom Number

Cha

rge

hfsto3g

hf321g

hf631g

hf6311g

ProprionitrileProprionitrile

1

2

3

4

5678

9

Page 17: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Basis Set Dependence of MUL, AIM and ESP Basis Set Dependence of MUL, AIM and ESP with DFT Methodswith DFT Methods

Proprionitrile Mulliken Charge via DFT Method at Optimal Geometry

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0 1 2 3 4 5 6 7 8 9 10

Atom Number

Ch

arg

e

blypsto3g

blyp631g

blyp6311g

blyp6311g+

blyp6311g++

blyp6311g++dp

Proprionitrile AIM Charges via DFT Method at Optimal Geometry

-1.5

-1

-0.5

0

0.5

1

-0.5 0.5 1.5 2.5 3.5 4.5 5.5 6.5 7.5 8.5 9.5

Atom Number

Cha

rge

blypsto3g

blyp631g

blyp6311g

blyp6311g+

blyp6311g++

blyp6311g++dp

Propionitrile ESP Charge via DFT Method at Optimal Geometry

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0 2 4 6 8 10

Atom Number

Ch

arg

e

blypsto3g

blyp631g

blyp6311g

blyp6311g+

blyp6311g++

blyp6311g++dp

Page 18: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Dihedral Angle Dependence of Charges on Atoms in Dihedral Angle Dependence of Charges on Atoms in Proprionitrile Using MUL, AIM and ESP with HF Proprionitrile Using MUL, AIM and ESP with HF MethodsMethods

Proprionitrile Mulliken Charges via Hartree-Fock Method at Varying Dihedral Angles

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

0 2 4 6 8 10

Atom Number

Ch

arg

e

15 Degrees

60 Degrees

105 Degrees

150 Degrees

195 DegreesPropionitrile AIM Charges via Hartree-Fock

Method at Varying Dihedral Angles

-1.5

-1

-0.5

0

0.5

1

0 2 4 6 8 10

Atom Number

Cha

rge

15Degrees60Degrees105Degrees150Degrees195Degrees

Proprionitrile ESP Charges via Hartree-Fock Method at Varying Dihedral Angles

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0 2 4 6 8 10

Atom Number

Ch

arg

e

15Degrees60Degrees105Degrees150Degrees195Degrees

Page 19: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Dihedral Angle Dependence of Charges on Dihedral Angle Dependence of Charges on Atoms in Proprionitrile Using MUL, AIM and Atoms in Proprionitrile Using MUL, AIM and ESP with DFT MethodsESP with DFT Methods

Proprionitrile Mulliken Charges via DFT Method at Varying Dihedral Angle

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

0 2 4 6 8 10

Atom Number

Ch

arg

e

15 Degrees

60 Degree

105 degree

150 degree

195 degree Proprionitrile AIM Charges via DFT Methods at Varying Dihedral Angle

-1

-0.8-0.6

-0.4-0.2

00.2

0.40.6

0.8

0 2 4 6 8 10

Atom Number

Ch

arg

e

15Degrees60Degree105degree150degree195degree

Proprionitrile ESP Charges via DFT Method at Varying Dihedral Angle

-0.6

-0.4

-0.2

0

0.2

0.4

0 2 4 6 8 10

Atom Number

Ch

arg

e

15Degrees60 Degree

105degree150degree195degree

Page 20: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

GlycineGlycine

12

3

4

5

6

7

8

9

10

Page 21: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Basis Set Dependence of Charges on Basis Set Dependence of Charges on Atoms in Glycine Using a Mulliken Atoms in Glycine Using a Mulliken Population AnalysisPopulation Analysis

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1

1 2 3 4 5 6 7 8 9 10

atom

ch

arg

e

HF321

HF631

HF6311

DFT631

DFT6311++d

DFT6311++dp

Page 22: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Basis Set Dependence of Charges Basis Set Dependence of Charges on Atoms in Glycine Using AIMon Atoms in Glycine Using AIM

-1.3

-0.8

-0.3

0.2

0.7

1.2

1 2 3 4 5 6 7 8 9 10

atom

ch

arg

e

HF321

HF631

HF6311

DFT631

DFT6311++d

DFT6311++dp

Page 23: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Basis Set Dependence of Charges Basis Set Dependence of Charges on Atoms in Glycine Using ESPon Atoms in Glycine Using ESP

-1.5

-1

-0.5

0

0.5

1

1.5

1 2 3 4 5 6 7 8 9 10

atom

ch

arg

e

HF321

HF631

HF6311

DFT631

DFT6311++d

DFT6311++dp

Page 24: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Glycine – Different Dihedral Angles

Optimized 45º

90º

Page 25: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Dihedral Angle Dependence of Dihedral Angle Dependence of Charges on Atoms in Glycine Using Charges on Atoms in Glycine Using MUL with DFTMUL with DFT

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

1 2 3 4 5 6 7 8 9 10

atom

ch

arg

e

optimized

45 dihedral

90 dihedral

Page 26: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Dihedral Angle dependence of Dihedral Angle dependence of Charges on Atoms in Glycine Using Charges on Atoms in Glycine Using AIM with DFTAIM with DFT

-1.5

-1

-0.5

0

0.5

1

1.5

1 2 3 4 5 6 7 8 9 10

atom

ch

arg

e optimized

45 dihedral

90 dihedral

Page 27: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Dihedral Angle dependence of Dihedral Angle dependence of Charges on Atoms in Glycine Using Charges on Atoms in Glycine Using ESP with DFTESP with DFT

-1.5

-1

-0.5

0

0.5

1

1.5

1 2 3 4 5 6 7 8 9 10

atom

ch

arg

e optimized

45 dihedral

90 dihedral

Page 28: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Basis Set Dependence of Charges on Basis Set Dependence of Charges on Atoms in Serine Using MUL, AIM and Atoms in Serine Using MUL, AIM and ESP with Hartree-Fock MethodsESP with Hartree-Fock Methods

Atomic charge using Hartree-Fock and Mulliken method for serine as a function of basis set

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1

1.2

1 2 3 4 5 6 7 8 9 10 11 12 13 14ato

mic

ch

arg

e

HF STO-3G MUL

HF 321-G MUL

HF 6311-G d MUL

Atomic charge using Hartree-Fock and AIM for serine as a function of basis set

-1.5

-1

-0.5

0

0.5

1

1.5

2

1 2 3 4 5 6 7 8 9 10 11 12 13 14

ato

mic

ch

arg

e

HF STO-3G AIM

HF 321-G AIM

HF 6311-G d AIM

Atomic charge using Hartree-Fock and ESP method for serine as a function of basis set

-1.5

-1

-0.5

0

0.5

1

1.5

1 2 3 4 5 6 7 8 9 10 11 12 13 14

ato

mic

ch

arg

eHF STO-3G ESP

HF 321-G ESP

HF 6311-G d ESP

Page 29: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Basis Set Dependence of Charges on Basis Set Dependence of Charges on Atoms in Serine Using MUL, AIM and Atoms in Serine Using MUL, AIM and ESP with Density Functional Theory ESP with Density Functional Theory MethodsMethods

Atomic charge using DFT and Mulliken method for serine as a function of basis set

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1

1 2 3 4 5 6 7 8 9 10 11 12 13 14

ato

mic

ch

arg

e

DFT STO-3G MUL

DFT 321-G MUL

DFT 6311-G d MUL

Atomic charge using DFT and AIM method for serine as a function of basis set

-1.5

-1

-0.5

0

0.5

1

1.5

2

1 2 3 4 5 6 7 8 9 10 11 12 13 14

ato

mic

ch

arg

e

DFT STO-3G AIM

DFT 321-G AIM

DFT 6311-G d AIM

Atomic charge using DFT and ESP method for serine as a function of basis set

-1.5

-1

-0.5

0

0.5

1

1 2 3 4 5 6 7 8 9 10 11 12 13 14a

tom

ic c

ha

rge

DFT STO-3G ESP

DFT 321-G ESP

DFT 6311-G d ESP

Page 30: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Comparison of methods using 6311-G Comparison of methods using 6311-G d basis set using DFT and HFd basis set using DFT and HF

Atomic charge of sering using Mulliken with DFT and HF

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1

1 2 3 4 5 6 7 8 9 10 11 12 13 14

HF 6311-G d MUL

DFT 6311-G d MUL

Atomic charge of serine using AIM with DFT and HF

-1.5

-1

-0.5

0

0.5

1

1.5

2

1 2 3 4 5 6 7 8 9 10 11 12 13 14

ato

mic

ch

arg

e

HF 6311-G d AIM

DFT 6311-G d AIM

Atomic charge of serine using ESP with DFT and HF

-1.5

-1

-0.5

0

0.5

1

1 2 3 4 5 6 7 8 9 10 11 12 13 14

atom

ic c

harg

eHF 6311-G d ESP

DFT 6311-G d ESP

Page 31: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Basis Set Dependence of Charges on Basis Set Dependence of Charges on Atoms in Propyl Aldehyde Using MUL, Atoms in Propyl Aldehyde Using MUL, AIM and ESP with Hartree-Fock AIM and ESP with Hartree-Fock Methods at theta~2.318Methods at theta~2.318

Atomic charge using Hartree-Fock and Mulliken method for propyl aldehyde as a function of basis set

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

1 2 3 4 5 6 7 8 9 10

ato

mic

ch

arg

e

HF STO-3G MUL

HF 321-G MUL

HF 6311-G d MUL

Atomic charge using Hartree-Fock and AIM method for propyl aldehyde as a function of basis set

-1.4

-1.2

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

1 2 3 4 5 6 7 8 9

ato

mic

ch

arg

e

HF STO-3G AIM

HF 321-G AIM

HF 6311-G d AIM

Atomic charge using Hartree-Fock and ESP method for propyl aldehyde as a function of basis set

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

0.1

0.2

1 2 3 4 5 6 7 8 9

ato

mic

ch

arg

e

HF STO-3G ESP

HF 321-G ESP

HF 6311-G d ESP

Page 32: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Comparison of Mulliken and Comparison of Mulliken and AIM using HF and DFT methodsAIM using HF and DFT methods

Mulliken vs. AIM for propyl aldehyde

-1.5

-1

-0.5

0

0.5

1

1.5

1 2 3 4 5 6 7 8 9 10

E HF 321-G MUL

E HF 6311-G d MUL

E B3LYP 6311-G d MUL

E HF 321-G AIM

E HF 6311-G d AIM

E B3LYP 6311-G d AIM

Page 33: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Basis Set Dependence of Charges on Basis Set Dependence of Charges on Atoms in Propyl Aldehyde Using MUL, Atoms in Propyl Aldehyde Using MUL, AIM and ESP with Density Functional AIM and ESP with Density Functional Theory MethodsTheory Methods

Atomic charge using DFT and AIM method for propyl aldehyde as a function of basis set

-1.5

-1

-0.5

0

0.5

1

1 2 3 4 5 6 7 8 9 10

ato

mic

ch

arg

e

B3LYP STO-3G AIM

B3LYP 321-G AIM

B3LYP 6311-G d AIM

Atomic charge using DFT and ESP method for propyl aldehyde as a function of basis set

-1.5

-1

-0.5

0

0.5

1

1 2 3 4 5 6 7 8 9 10

ato

mic

ch

arg

e

B3LYP STO-3G ESP

B3LYP 321-G ESP

B3LYP 6311-G d ESP

Atomic charge using DFT and Mulliken method for propyl aldehyde as a function of basis set

-0.7

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

1 2 3 4 5 6 7 8 9 10

ato

mic

ch

arg

e

B3LYP STO-3GMULB3LYP 321-G MUL

B3LYP 6311-G dMUL

Page 34: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Basis Set Dependence of Charges on Basis Set Dependence of Charges on Atoms in Propyl Aldehyde Using MUL, Atoms in Propyl Aldehyde Using MUL, AIM and ESP with Hartree-Fock AIM and ESP with Hartree-Fock Methods at theta~127.46Methods at theta~127.46

Atomic charge using Hartree-Fock and Mulliken method for propyl aldehyde (127.46) as a function of basis set

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

1 2 3 4 5 6 7 8 9 10

ato

mic

ch

arg

e

HF STO-G MUL

HF 321-G MUL

HF 6311-G d MUL

Atomic charge using Hartree-Fock amd AIM method for propyl aldehyde (127.46) as a function of basis set

-1.5

-1

-0.5

0

0.5

1

1.5

1 2 3 4 5 6 7 8 9 10

ato

mic

ch

arg

e

HF STO-3G AIM

HF 321-G AIM

HF 6311-G d AIM

Atomic charge using DFT and ESP method for propyl aldehyde (127.46) as a function of basis set

-0.5

-0.4

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

1 2 3 4 5 6 7 8 9 10at

om

ic c

har

ge

B3LYP STO-3G ESP

B3LYP 321-G ESP

B3LYP 6311-G d ESP

Page 35: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Basis Set Dependence of Charges on Basis Set Dependence of Charges on Atoms in Propyl Aldehyde Using MUL, Atoms in Propyl Aldehyde Using MUL, AIM and ESP with DFT Methods at AIM and ESP with DFT Methods at theta~127.46theta~127.46

Atomic charge using DFT and Mulliken method for propyl aldehyde (127.46) as a function of basis set

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

1 2 3 4 5 6 7 8 9 10

B3LYP STO-3G MUL

B3LYP 321-G MUL

B3LYP 6311-G d MUL

Atomic charge using DFT and AIM method for propyl aldehyde (127.46) as a function of basis set

-1.5

-1

-0.5

0

0.5

1

1.5

1 2 3 4 5 6 7 8 9 10

ato

mic

ch

arg

e

B3LYP STO-3G AIM

B3LYP 321-G AIM

B3LYP 6311-G d AIM

Atomic charge using DFT and ESP method for propyl aldehyde (127.46) as a function of basis set

-0.5

-0.4

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

1 2 3 4 5 6 7 8 9 10at

om

ic c

har

ge

B3LYP STO-3G ESP

B3LYP 321-G ESP

B3LYP 6311-G d ESP

Page 36: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Comparison of Charges on Atoms in Comparison of Charges on Atoms in Propyl Aldehyde Using MUL and AIM as Propyl Aldehyde Using MUL and AIM as a function rotating carbonyl groupa function rotating carbonyl group

Page 37: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Charges on Atoms in Propyl Aldehyde Charges on Atoms in Propyl Aldehyde Using MUL and AIM with HF and DFT Using MUL and AIM with HF and DFT Methods as a function of rotating Methods as a function of rotating carbonyl groupcarbonyl group

Mulliken charges as a function of dihedral angle of carbonyl group

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

1 2 3 4 5 6 7 8 9 10

E HF 321-G =-2.318

E HF 6311-G d =-2.318

E B3LYP 6311-G d =-2.318

E HF 321-G =-127.875

E HF 6311-G d =-127.875

E B3LYP 6311-G d =-127.875

AIM atomic charges as a function of dihedral angle of the carbonyl group

-1.5

-1

-0.5

0

0.5

1

1.5

1 2 3 4 5 6 7 8 9 10

Page 38: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Comparison of single and Comparison of single and double bonded propyl double bonded propyl aldehyde!aldehyde!

Mulliken vs. AIM vs. ESP for prop// di=0.000

-1.5

-1

-0.5

0

0.5

1

1 2 3 4 5 6 7 8

MUL1

AIM1

ESP1

Comparison of HF and DFT using Mulliken Method for propyl aldehyde with single and double bonds

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1 2 3 4 5 6 7 8 9 10

ato

mic

ch

arg

e

321-G MUL HF/

321-G MUL DFT/

321-G MUL HF//

Page 39: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Comparison of charges using Mulliken Comparison of charges using Mulliken and AIM with HF and DFT @ dihedral and AIM with HF and DFT @ dihedral angle = 127.46angle = 127.46

Mulliken vs. AIM for butylaldehyde @ 127.46

-1.5

-1

-0.5

0

0.5

1

1.5

1 2 3 4 5 6 7 8 9 10 11 12 13

M1

M2

M3

AIM1

AIM2

AIM3

Page 40: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Comparison of Mulliken and AIM for Comparison of Mulliken and AIM for Butyl Aldehyde using HF and DFT @ Butyl Aldehyde using HF and DFT @ dihedral angle ~0.000dihedral angle ~0.000

MUL VS AIM FOR BUTYL @0.065

-1.5

-1

-0.5

0

0.5

1

1.5

1 2 3 4 5 6 7 8 9 10 11 12 13

M1

M2

M3

AIM1

AIM2

AIM3

Page 41: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Comparison of charge as a function of Comparison of charge as a function of dihedral angle for butyl aldehyde using dihedral angle for butyl aldehyde using HF and DFT with AIM and MULHF and DFT with AIM and MUL

Charge as a function of dihedral angle for 6311-G d using HF and DFT with AIM

-1.5

-1

-0.5

0

0.5

1

1.5

1 2 3 4 5 6 7 8 9 10 11 12 13

ato

mic

ch

arg

e

6311-G d HF AIM 127.46

6311-G d DFT AIM 127.46

6311-G d HF AIM ~0.00

6311-G d DFT AIM ~0.00

Charge as a function of dihedral angle using HF and DFT with Mulliken

-0.7

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

1 2 3 4 5 6 7 8 9 10 11 12 13

ato

mic

ch

arg

e

6311-Gd HF MUL127.466311-G d DFT MUL127.466311-G d HF MUL~0.006311-G d DFT MUL~0.00

Page 42: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Propane Mulliken Charges (Basis Set 6-311gd)

-2

-1.5

-1

-0.5

0

0.5

1

C1 C2 C3 H4 H5 H6 H7 H8 H9 H10 H11

Atom Number

Ch

arg

e B3LYP/6-311gd

MP2/6-311gd

HF/6-311gd

PropaneMulliken Charges via HF, Post HF

and DFT MethodsPropane Mulliken Charges

-1.5

-1

-0.5

0

0.5

1

C1 C2 C3 H4 H5 H6 H7 H8 H9 H10 H11

Atom Number

Cha

rge

B3LYP/6-31gd

MP2/6-31gd

HF/6-31gd

Page 43: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Propane Electrostatic Charges (Basis Set 6-31gd)

-1

-0.5

0

0.5

1

1.5

C1 C2 C3 H4 H5 H6 H7 H8 H9 H10 H11

Atom Number

Ch

arg

e B3LYP/6-31g

MP2/6-31g

HF/6-31g

Propane Electrostatic Charges(Basis Set 6-311gd)

-1.5

-1

-0.5

0

0.5

1

1.5

C1 C2 C3 H4 H5 H6 H7 H8 H9 H10 H11

Atom Number

Ch

arg

e B3LYP/6-311gd

MP2/6-311gd

HF/6-311gd

Propane Electrostatic Charges via HF, Post HF and

DFT Methods

Page 44: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Atoms in Molecules Charges (Basis Set 6-31gd)

-0.1

0

0.1

0.2

0.3

C1 C2 C3 H4 H5 H6 H7 H8 H9 H10 H11

Atom Number

C h

a r

g e

B3LYP/6-31g

MP2/6-31g

HF/6-31g

Atoms in Molecules Charges (Basis Set 6-311gd)

-0.1

-0.05

0

0.05

0.1

0.15

0.2

C1 C2 C3 H4 H5 H6 H7 H8 H9 H10 H11

Atom Number

C h

a r

g e

B3LYP/6-311gd

MP2/6-311gd

HF/6-311gd

Atoms in Molecules via HF, Post HF and DFT Methods

Page 45: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Charge Type Analysis Propane

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

C1 C2 C3 H4 H5 H6 H7 H8 H9 H10 H11

Atom Number

Ch

arg

e A HF/6-31g

E HF/6-31g

M HF/6-31gd

Charge Type Analysis Propane

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

C1 C2 C3 H4 H5 H6 H7 H8 H9 H10 H11

Atom Number

Ch

arg

e A HF/6-311gd

E HF/6-311gd

M HF/6-311gd

Conformational Dependence of Charge

(Basis Set 6-31gd)

H50.20

2 0.079 0.013

H60.20

7 0.077 0.016

H70.21

3 0.101 0.022

H80.18

2 -0.02 -0.004

H9 0.21 -0.007 0.021

H100.17

7 -0.012 0.004

H110.20

2 0.06 0.033

H120.37

2 0.406 0.504

Page 46: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

CTA

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

C1 C2 C3 H4 H5 H6 H7 H8 H9 H10 H11

Atom Number

Char

ge

A MP2/6-31gd

E MP2/6-31gd

M MP2/6-31gd

CTA

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

C1

C2

C3

H4

H5

H6

H7

H8

H9

H10

H11

Atom Number

Cha

rge A MP2/6-311gd

E MP2/6-311gd

M MP2/6-311gd

Conformational Dependence of Charge(Basis Set 6-311gd)

CTA

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

C1 C2 C3 H4 H5 H6 H7 H8 H9 H10 H11

Atom Number

Cha

rge

A B3LYP/6-31g

E B3LYP/6-31g

M B3LYP/6-31gd

CTA

-1.2

-1

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

C1 C2 C3 H4 H5 H6 H7 H8 H9 H10 H11

Atom Number

Char

ge

A B3LYP/6-311gd

E B3LYP/6-311gd

M B3LYP/6-311gd

Page 47: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

PropanolMulliken Charges via

HF, Post HF and DFT Methods

Mullikan Charges

-2.5

-2

-1.5

-1

-0.5

0

0.5

1

1.5

C1 C2 C3 H4 H5 H6 H7 H8 H9 H10 O11 H12

Atom Number

Ch

arg

e B3LYP/6-31gd

MP2/6-31gd

HF/6-31gd

Mullikan Charges

-2.5

-2

-1.5

-1

-0.5

0

0.5

1

1.5

C1 C2 C3 H4 H5 H6 H7 H8 H9 H10 O11 H12

Atom

Ch

arg

e B3LYP/6-311gd

MP2/6-311gd

HF/6-311gd

Page 48: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

ESP Charges Propanol (Basis Set 6-311gd)

-3

-2

-1

0

1

2

C1 C2 C3 H4 H5 H6 H7 H8 H9 H10 O11 H12

Atom Number

Char

ge

B3LYP/6-311gd

MP2/6-311gd

HF/6-311gd

Electrostatic Charges Propanol (Basis Set 6-31gd)

-3

-2

-1

0

1

2

C1 C2 C3 H4 H5 H6 H7 H8 H9 H10 O11 H12

Atom Number

Cha

rge

B3LYP/631gdMP2/631gd

HF/631gd

Propanol’s Electrostatic Charges via HF, Post HF and

DFT Methods

Page 49: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Atoms in Molecules Charges Propanol (Basis Set 6-31gd)

-4

-2

0

2

4

C1 C2 C3 H4 H5 H6 H7 H8 H9 H10 O11 H12

Atom Number

Cha

rge

B3LYP/6-31gd

MP2/6-31gd

HF/6-31gd

Atoms in Molecules Charges Propanol (Basis Set 6-311gd)

-4

-2

0

2

C1 C2 C3 H4 H5 H6 H7 H8 H9 H10 O11 H12

Atom Number

Char

ge

B3LYP/6-311gd

MP2/6-311gd

HF/6-311gd

Propanol’s Atoms in Molecules Charges via HF, Post HF and DFT Methods

Page 50: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Charge Type Analysis Propanol

-3

-2

-1

0

1

2

C1 C2 C3 H4 H5 H6 H7 H8 H9 H10 O11 H12

Atom Number

Ch

arg

e A HF/6-311gd

E HF/6-311gd

M HF/6-311gd

Charge Type Analysis Propanol

-3

-2

-1

0

1

2

C1 C2 C3 H4 H5 H6 H7 H8 H9 H10 O11 H12

Atom Number

Ch

arg

e A MP2/6-311gd

E MP2/6-311gd

M MP2/6-311gd

Charge Type Analysis Propanol

-2.5

-2

-1.5

-1

-0.5

0

0.5

1

1.5

Atom Number

Ch

arg

e A B3LYP/6-311gd

E B3LYP/6-311gd

M B3LYP/6-311gd

A Comparsion of Propanol at Varying Dihedral Angles Conformational Dependence of Charge

(Basis Set 6-311gd)Charge Type Analysis forPropanol Dihedral Angle HF/6-

311gd

-3

-2.5

-2

-1.5

-1

-0.5

0

0.5

1

1.5

2

Atom Number

Ch

arg

e

AIM

ESP

Mulliken

Charge Type Analysis for Propanol Dihedral AngleMP2/6-311gd

-3

-2

-1

0

1

2

Atom NumberC

ha

rge

AIM

ESP

Mulliken

Charge Type Analysis for Propanol

Dihedral Angle B3LYP/6-311gd

-3

-2

-1

0

1

2

C1 C2 C3 H4 H5 H6 H7 H8 H9 H10 O11 H12

Atom Number

Cha

rge AIM

ESP

Mulliken

Page 51: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

CC22HH44FF22

Page 52: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Mulliken (100)

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

1 2 3 4 5 6 7 8

Atom

Ch

arg

e

MK_100_321G_B3LYP

MK100_HF631G

MK_100_B3LYP_G311G

MK_100_HF_6311G

AIM (100)

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1 2 3 4 5 6 7 8

Atom

AIM_100_321G_B3LYP

AIM_100_HF631G

AIM_100_B3LYP_G311G

AIM_100_HF_6311G

ESP (100)

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

1 2 3 4 5 6 7 8

Atom

Ch

arg

e

ESP_100_321G_B3LYP

ESP_100_HF631G

ESP_100_B3LYP_G311G

ESP_100_HF_6311G

Page 53: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

STDEV (100,various basis sets)

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.1

1 2 3 4 5 6 7 8

Atom

SD

AIM_100_STDEV

MK_100_STDEV

ESP_100_STDEV

Page 54: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Mulliken (75)

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

1 2 3 4 5 6 7 8

Atom

Ch

arg

e

MK_75_321G_RB3LYP

MK75_631G_RHF

MK_75_HF_321G

MK_75_631G_B3LYP

ESP (75)

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

1 2 3 4 5 6 7 8

Atom

Ch

arg

e

ESP_75_321G_RB3LYP

ESP_75_631G_RHF

ESP_75_HF_321G

ESP_75_631G_B3LYP

AIM (75)

-0.8-0.6-0.4-0.2

0

0.20.40.60.8

1 2 3 4 5 6 7 8

Atom

Ch

arg

e

AIM_75_321G_RB3LYP

AIM_75_631G_RHF

AIM_75_HF_321G

AIM_75_631G_B3LYP

Page 55: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

STDEV (75,various basis sets)

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

1 2 3 4 5 6 7 8

Atom

SD

AIM_75_STDEV

MK_75_STDEV

ESP_75_STDEV

Page 56: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

AIM (120)

-0.8

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1 2 3 4 5 6 7 8

Atom

Ch

arg

e

AIM_120_321G_HF

AIM_120_631G_HF

AIM_120_B3LYP_631G

AIM_120_321G_B3LYP

Mulliken (120)

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

1 2 3 4 5 6 7 8

Atom

Ch

arg

e

MK_120_321G_HF

MK_120_631G_HF

MK_120_B3LYP_631G

MK_120_321G_B3LYP

ESP (120)

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

1 2 3 4 5 6 7 8

Atom

Ch

arg

e

ESP_120_321G_HF

ESP_120_631G_HF

ESP_120_B3LYP_631G

ESP_120_321G_B3LYP

Page 57: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

STDEV (120,various basis sets)

0

0.02

0.04

0.06

0.08

0.1

0.12

1 2 3 4 5 6 7 8

Atom

SD

AIM_120_STDEV

MK_120_STDEV

ESP_120_STDEV

Page 58: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

AIM for different angles

-0.6

-0.4

-0.2

0

0.2

0.4

0.6

1 2 3 4 5 6 7 8

Atom

Ch

arg

e

AIM_75_321G_B3LYP

AIM_100_321G_B3LYP

AIM_120_321G_B3LYP

Page 59: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

ESP (for different angles)

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

1 2 3 4 5 6 7 8

Atom

Ch

arg

eESP_75_321G_B3LYP

ESP_100_321G_B3LYP

ESP_120_321G_B3LYP

Page 60: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

MK (for different angles)

-0.4

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

1 2 3 4 5 6 7 8

Atom

Ch

arg

e MK_75_321G_B3LYP

MK_100_321G_B3LYP

MK_120_321G_B3LYP

Page 61: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

Error 2070Error 2070

• WARNING: RMS ERROR HAS WARNING: RMS ERROR HAS INCREASED. NEWTON STEP FAILED INCREASED. NEWTON STEP FAILED FOR SURFACE SHEET n.FOR SURFACE SHEET n.

• Many molecules resulted in error 2070 Many molecules resulted in error 2070 in Gaussian98 when running AIM. (i.e. in Gaussian98 when running AIM. (i.e. ethyl formate, alanine, cysteine)ethyl formate, alanine, cysteine)

Page 62: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

References:References:

1. Politzer, P.; Harris, R.R. J. Chem.Phys. 1970, 92, 6451.

2. McQuarrie, D.A.; Simon, J.D. Physical Chemistry: A Molecular Approach. University Science Books: Sausalito, California, 1997.

3. http://www.chemistry.mcmaster.ca/faculty/bader/aim/aim_1.html

Page 63: Comparative Study of Three Methods of Calculating Atomic Charge in a Molecule

AcknowledgmentsAcknowledgments• Inspiration for Project:Inspiration for Project:

Dr. Sergio Aragon and Dr. Mario BlancoDr. Sergio Aragon and Dr. Mario Blanco

(Their debate about Mulliken vs AIM (Their debate about Mulliken vs AIM method assignment of charges on method assignment of charges on atoms in molecules made this project atoms in molecules made this project happen)happen)

• PASI/CaltechPASI/Caltech