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TRANSCRIPT
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1
Transition Metals in Coordination Chemistry IA VIIIA
1
H 1.008 IIA
IIIA IVA VA VIA VIIA
2
He 4.003
3
Li 6.941
4
Be 9.012
IIIB IVB VB VIB VIIB VIII IB IIB
5
B 10.811
6
C 12.011
7
N 14.007
8
O 15.999
9
F 18.998
10
Ne 20.180
11
Na 22.990
12
Mg 24.305
13
Al 26.982
14
Si 28.086
15
P 30.974
16
S 32.065
17
Cl 35.453
18
Ar 39.948
19
K 39.098
20
Ca 40.078
21
Sc 44.956
22
Ti 47.867
23
V 50.942
24
Cr 51.996
25
Mn 54.938
26
Fe 55.845
27
Co 58.933
28
Ni 58.693
29
Cu 63.546
30
Zn 65.409
31
Ga 69.723
32
Ge 72.64
33
As 74.921
34
Se 78.96
35
Br 79.904
36
Kr 83.798
37
Rb 85.468
38
Sr 87.62
39
Y 88.906
40
Zr 91.224
41
Nb 92.906
42
Mo 95.94
43
Tc (98)
44
Ru 101.07
45
Rh 102.906
46
Pd 106.42
47
Ag 107.868
48
Cd 112.411
49
In 114.818
50
Sn 118.710
51
Sb 121.760
52
Te 127.60
53
I 126.904
54
Xe 131.293
55
Cs 132.905
56
Ba 137.327
71
Lu 174.967
72
Hf 178.49
73
Ta 180.948
74
W 183.84
75
Re 186.207
76
Os 190.23
77
Ir 192.217
78
Pt 195.078
79
Au 196.967
80
Hg 200.59
81
Tl 204.383
82
Pb 207.2
83
Bi 208.980
84
Po (209)
85
At (210)
86
Rn (222)
87
Fr (223)
88
Ra 226.025
103
Lr (262)
104
Rf (261)
105
Db (262)
106
Sg (266)
107
Bh (264)
108
Hs (277)
109
Mt (268)
110
Ds (281)
111
Rg (272)
112
C (285)
113
C 12.011
114
C (289)
115
C 12.011
116
C (289)
117
C 12.011
118
57
La 138.906
58
Ce 140.116
59
Pr 140.908
60
Nd 144.24
61
Pm (145)
62
Sm 150.36
63
Eu 151.964
64
Gd 157.25
65
Tb 158.925
66
Dy 162.500
67
Ho 164.930
68
Er 167.259
69
Tm 168.934
70
Yb 173.04
89
Ac 227.028
90
Th 232.038
91
Pa 231.036
92
U 238.029
93
Np 237.048
94
Pu (244)
95
Am (243)
96
Cm (247)
97
Bk (247)
98
Cf (251)
99
Es (252)
100
Fm (257)
101
Md (258)
102
No (259)
Cn (284) (289) (294) (294) (291)
d 6
d 5
Fe 4s 3d
Fe2+ 4s 3d
Fe3+ 4s 3d
d 10
d 9
Cu 4s 3d
Cu+ 4s 3d
Cu2+ 4s 3d
described by # valence d e–
d e– first row M2+ ions = Z – 20
Fl Lv
“Even when they are saturated in the sense of the older theory
of (primary) valence, the elementary atoms still possess sufficient
chemical affinity to bind other seemingly also saturated atoms and
groups of atoms, under generation of clearly defined atomic bonds.
This doctrine has now been so amply confirmed experimentally by
investigations of a very large number of molecular compounds which
are now called complex compounds, that we can make it the
starting-point of further developments.”
Alfred Werner 1913 Nobel Prize Lecture
Complex Compounds
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F– fluoro
Cl– chloro
Br– bromo
I– iodo
CN– cyano
1. anionic ligands a. most have –o ending:
NO2 – nitro
OCN– cyanato
SCN– thiocyanato
CO32– carbonato
C2O42– oxalato
CH3COO– acetato
S2O32– thiosulfato
OH– hydroxo
NCO– isocyanato
NCS– isothiocyanato
H– hydrido
N3– azido
O22– peroxo
NO3– nitrato
O2– oxo
S2– thio
SH– mercapto
N3– nitrido
acetylacetonato
2,4-pentanedionato
acac
dimethylglyoximato
DMG
Mn+
Mn+
Nomenclature
N N O HO
O-N-O – nitrito
nitrito - N nitrito - O
thiocyanato - S thiocyanato - N
cyanato - O cyanato - N
H
O O
CH3– methyl
C6H5– phenyl
CH2 = CH– enyl
b. hydrocarbon anion –yl ending
cyclopentadienyl Cp
pentamethylcyclopentadienyl Cp*
Nomenclature
1. anionic ligands
allyl
(– H+)
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a. usually compound’s name
ethylenediamine en
N N
N N
bipyridine bipy
o-phenanthroline o-phen
H2O aqua
NH3 ammine
CO carbonyl
b. exceptions
NO nitrosyl
N2 dinitrogen
O2 dioxygen
H2N NH2
Nomenclature
2. neutral ligands
tri(R)phosphine
PPh3 P
R R
R
ethene (ethylene)
CH2
CH2
M
R = phenyl
PMe3 methyl
PtBu3 t-butyl
c. oxidation state
Roman numerals in parentheses: Stock notation
a. cationic or neutral complex
metal name unchanged
b. anionic complex
L form (usually like symbol) with –ate ending
cuprate ferrate aurate argenate
Alfred Stock
German
(1876-1946)
Nomenclature
3. metal
Cr3+
Fe2–
Ni
chromium(III)
nickel(0)
iron(–II)
no space!
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6. # of each ligand type with prefixes
a. short names di, tri, tetra, penta
b. long names bis, tris, tetrakis, pentakis
4. order
a. cation, anion
b. ligands first; attach directly to metal name
c. alphabetical order
5. a. neutral ligand name in parentheses
except for H2O, NH3, CO, NO
b. short anions not in parentheses
c. long anions (4 syllables) in parentheses
d. bridging ligands (2 metal ions) μ- (mu) before name
Putting it Together
[Co(NH3)6](NO3)3
Na[PtCl3(NH3)]
[Ni(en)2]Cl2
[Ni(CH2CH2)2(NH3)2]2+
[Pt(NH3)2Cl2]
Naming Examples
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( )
sepulchrate
tomb or burial chamber
L sepulcrum “to bury”
[Co(sep)] 3+
cryptate
L crypta “concealed”
burial vault
sepulchre
crypt
Laboratory Synthesis
Co
NH
NH
HN
HN
HN
HN
N
N
similar to VSEPR
2 linear
Ph3P
PPh3
PPh3
Pt
3 trigonal planar
L
M
L L
L
4 Td
common Ni2+, Pd2+, Pt2+, Cu2+
L
M L L
L
or square planar
L M L
L
L
L
5 square pyramid
or trigonal bipyramid
6 Oh or trigonal prism isomers…
Geometry
M L
L L
L
L
M L
L L
L
L
L
M
L L
L L
L
L
rare Pt0
[H3N–Ag–NH3]+
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[Co(NH3)5NO2]2+ [Co(NH3)5ONO]2+
[Pd(PPh3)2(NCS)2] [Pd(PPh3)2(SCN)2]
Linkage Isomers
[PtBr2(NH3)4]Cl2
Coordination Isomers
[Co(NH3)5Br]SO4 [Co(NH3)5SO4]Br
[PtCl2(NH3)4]Br2
[Co(en)3][Cr(CN)6] [Cr(en)3][Co(CN)6]
[Pt(NH3)4][PtCl6] [Pt(NH3)4Cl2][PtCl4]
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Geometrical Isomers
NH3
Pt NH3 Cl
Cl
Pt
Cl
Cl Cl
Cl
NH3
NH3
NH3
Pt Cl Cl
NH3
Pt
Cl
Cl NH3
NH3
Cl
Cl
Co
Cl
Cl Cl
NH3
NH3
NH3
Co
H3N
Cl Cl
NH3
NH3
Cl
Conformational Isomers
Ni
NC
NC CN
CN
CN
NC Ni
CN
CN
CN
CN
[Ni(CN)5]3–
[Cr(C2O4)3]3–
Optical Isomers
Cr
O
O O
O
O
O
O
O O
O
O
O
Cr
L D righthand helix lefthand helix
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bis(ethylenediamine)nickel(II)
cis-di(ethylene)diamminenickel(II)
Formula Examples
sodium pentacyanonitrosylferrate(II)
sodium pentacyanonitrosylferrate(IV)
sodium pentacyanonitrosylferrate(III)
μ-hydroxobis[pentaamminechromium(III)] chloride
Bonding in Coordination Compounds
theory needs to explain special properties:
magnetism, spectroscopy (color), reactivity (labile, inert)
4. Ligand Field Theory (LFT)
3. Crystal Field Theory (CFT)
Carl Ballhausen
Danish
1950’s
John H. van Vleck
American
1932
starts with CFT, adds covalency
d orbitals
1. VB hybridization
2. MO most rigorous
assumes ionic bonding;
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Oh Crystal Field Splitting
x
y
dxy
x
z
dxz dyz
x
y
dx2 – y2
x
z
dz2
x
y
z
y
z
3. nature of L
X very weak
S, O weak
N, P moderate
C very strong
Crystal Field Splitting: Magnitude of D
I– < Br– < OCrO32– < Cl– SCN– < N3
– < F– SSO32– urea (O)
< OCO22– < OCO2R
– < ONO– OH– < OSO32– < ONO2
– < O2CCO22–
< H2O < NCS– < glycine EDTA4– < pyridine NH3 < en < SO32–
< bipy < o-phen < NO2– < PPh3 < Cp < CN– < CO
[Cu
(OC
O2 P
h)
6 ]2+
[Cu
(H2 O
)6 ]
2+
[Cu
(ED
TA
)6 ]
2+
Spectrochemical Series
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yz xz
z2
x2 – y2 xy
xy yz xz
x2 – y2 z2
xy
Other Geometries
linear
z2
yz xz
x2 – y2 xy
trigonal
yz xz
x2 – y2 xy
z2
tetrahedral square
planar
x2 – y2
trigonal
bipyramidal
z2
yz xz
square
pyramidal
x2 – y2
yz xz
z2
xy
octahedral
xy yz xz
x2 – y2 z2
center of
gravity
M M M M M M M
Crystal Field Stabilization Energy Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn
ΔH
La
ttic
e o
f M
Cl 2
(k
J/m
ole
)
d 0 d
1 d 2 d
3 d 4 d
5 d 6 d
7 d 8 d
9 d 10
d 0 d 1 d 2 d 3 d 4 d 5 d 6 d 7 d 8 d 9 d 10
80
85
90
95
100
105
110
115
Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn
M2
+ I
on
ic R
ad
ius
(pm
)
60
65
70
75
80
85
90
Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga
M3
+ I
on
ic R
ad
ius
(pm
)
d 0 d 1 d 2 d 3 d 4 d 5 d 6 d 7 d 8 d 9 d 10
–2900
–2800
–2700
–2600
–2500
–2400
–2300
–2200
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“A non-linear molecule in a degenerate electronic state will … undergo
distortion to … lower symmetry and lower E thereby removing degeneracy."
particularly important: Cu2+ d 9
Cu(NH3)62+ 4 Cu-N 2.07 Å
2 Cu-N 2.62 Å
Cu(DMG)2(H2O)2 4 Cu-N 1.94 Å
2 Cu-O 2.43 Å
Jahn-Teller Effect in Cu2+
CuCl2 4 Cu-Cl 2.30 Å
2 Cu-Cl 2.95 Å H
Cu
N
N N
N
OH2
OH2
O O
O O
H
Edward Teller
Hungarian - American
Hermann A. Jahn
English 1937
Jahn-Teller Effect in Cu2+
D3 symmetry at Cu2+
z2
x2– y2 xy
xz yz
dynamic Jahn-Teller distortion
all Cu–N bonds same length
Cu(MeTRI)22+
N
N
N
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M M M
M M M
Bonding Orbitals
A1g Eg
T1u
and dx2– y2) (M s) (M dz2
(M p)
absorption spectra from e– transitions between orbitals
d
s
p
t1u
a1g
eg
t2g
t1u*
a1g*
eg*
t2g
t1u
a1g
eg ligand
s SALC
t1u
a1g
eg
metal
orbitals
L M
M L
L L
d d TM color
Charge Transfer (CT)
IR-vis
UV-vis
intense: ε ≈ 104
M–L → M+L–
M–L → M–L+
UV
vis-UV
ligand e– structure Td Oh
ε ≈ 10–2 - 102 very weak:
Electronic Transitions TM complexes often highly colored: MO theory
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CT t2g2eg
1 t2g3
4T2g 4A2g
4T1g 4A2g
2Eg 4A2g
magnified
200 400 600 λ (nm)
0
2
4
log
ε
(50 000 cm–1) (25 000 cm–1) (17 000 cm–1)
UV-vis Spectrum of d 3 [Cr(NH3)6]
3+
d d
d d
L M
hn > Do hn = Do Do
Ti(H2O)63+
hn < Do
d1
0
1.0
2.0
3.0
4.0
12500 17500 22500 27500 cm–1
A
400 700
450
500
550
600
650
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d 2
1S
1G
3P
1D
3F
e2
t2e
t22
1A1 (1)
1E (2)
1T1 (3)
1T2 (3)
1A1 (1)
3T1 (9)
1E (2)
1T2 (3)
3A2 (3)
3T2 (9)
3T1 (9)
1A1 (1)
1E (2)
1T1 (3)
1T2 (3)
1A1 (1)
3T1 (9)
1E (2)
1T2 (3)
3A2 (3)
3T2 (9)
3T1 (9)
Spectroscopy
E/B
Ti V Cr Mn Fe Co Ni Cu
neutral: 560 580 790 720 805 780 1025
1+: 680 660 710 870 870 880 1040 1220
2+: 720 765 830 960 1060 1120 1080 1240
3+: 860 1030 1140
Zr Nb Mo Tc Ru Rh Pd Ag
250 300 460 600
450 260 440 670
540 530 620 830
Hf Ta W Re Os Ir Pt Au
280 350 370 850
440 480 470
Δo/B
Racah parameters
B DE terms of same
multiplicity
Δo
E
(45)
(1)
(9)
(9)
(5)
(21)
Yukito Satoru
Japanese
1954
Tanabe-Sugano Diagram
(6)
(15)
(24)
Do/B
E/B
0
10
20
30
40
50
60
70
80
0 10 20 30 40
d 2 Tanabe-Sugano Diagram
3A2g
3T1g
3T1g
1A1g
1T2g
1T1g
1Eg
3T2g
1T2g
1A1g 1Eg
3F
1D
3P
1G
1S
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d 3 Tanabe-Sugano Diagram
0
10
20
30
40
50
60
70
80
0 10 20 30 40 50
Do/B
E/B
4T2g
4A2g
2T2g
2Eg
2A1g
2T1g
4T1g
4T1g 2A2g
4F
4P
2G
2F
d 4 Tanabe-Sugano Diagram
0
10
20
30
40
50
60
70
80
0 10 20 30 40 50
Do/B
E/B
3A1g
3T1g
3T2g
5Eg
5T2g
1A1g
1T1g
3A2g 1A2g
5D
3H
3F, 3G
3D, 1I
1F
3P
1Eg 1T2g
1A2g 3A2g
3Eg
5Eg
3T1g
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d 5 Tanabe-Sugano Diagram
0
10
20
30
40
50
60
70
80
0 10 20 30 40 50
Do/B
E/B
2Eg
2T2g
2A2g, 2T1g
4A1g
4T1g
2A1g
4T1g 4A2g
4T2g
6A1g
6S
4G
2I
4F
4D
6A1g
2T2g
d 6 Tanabe-Sugano Diagram
0
10
20
30
40
50
60
70
80
0 10 20 30 40 50
Do/B
E/B
1T1g
1A1g
1Eg
3T1g
5T2g
3T2g
3T2g
5D
1F
3P
3H
5T2g
1A1g
3F, 3G
1G, 1I
1T2g
3A2g
1A1g 3A2g
1A2g
5Eg 3A2g
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d 7 Tanabe-Sugano Diagram
0
10
20
30
40
50
60
70
80
0 10 20 30 40 50
Do/B
E/B
2Eg
4T2g
4T1g
2T2g
4F
2G
2F
4P
4A2g 2A2g
2A1g 4T1g
2T1g
4T1g
d 8 Tanabe-Sugano Diagram
0
10
20
30
40
50
60
70
80
0 10 20 30 40
Do/B
E/B
3A2g
1T1g
1A1g
3T1g
3F
1G
1D
3T2g
1T2g 1A1g
3T1g
1T2g
1Eg 3P
1S
1Eg
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3A2g
3T1g
3T1g
1A1g
1T2g
1T1g
1Eg
3T2g
1T2g
1A1g 1Eg
3F
1D
3P
1G
1S
Do/B
E/B
0
10
20
30
40
50
60
70
80
0 10 20 30 40
0
1
2
3
4
5
6
7
8
9
10
10,000 15,000 20,000 25,000 30,000 35,000
cm–1
e
n1 n2
V(H2O)63+ d
2
absorbance bands:
n1 = 17,800 cm–1
n2 = 25,700 cm–1
(562 nm)
(389 nm)
Application of Tanabe-Sugano Diagram
Application of Tanabe-Sugano Diagram
Cr(H2O)63+ d
3
absorbance bands:
l1 = 578 nm
l2 = 406 nm
l3 = 300 nm
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
250 300 350 400 450 500 550 600 650
nm
A
l2 l3 l1
(17,300 cm–1)
(24,600 cm–1)
(33,000 cm–1)
0
10
20
30
40
50
60
70
80
0 10 20 30 40 50
Do/B
E/B
4T2g
4A2g
2T2g
2Eg
2A1g
2T1g
4T1g
4T1g 2A2g
4F
4P
2G
2F
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d 8 n2/n1 Ratio
1.2
1.3
1.4
1.5
1.6
1.7
1.8
0 5 10 15 20 25 30 35 40
Do/B
n2/n
1
magnified 0
2
4
log
ε
(50 000 cm–1) (25 000 cm–1) (17 000 cm–1)
UV-vis Spectrum of d 3 [Cr(NH3)6]
3+
0
10
20
30
40
50
60
70
80
0 10 20 30 40 50
Do/B
E/B
4T2g
4A2g
2T2g
2Eg
2A1g
2T1g
4T1g
4T1g 2A2g
4F
4P 2G
2F
200 400 600 λ (nm)
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Summary of HS Oh, Td TM Spectroscopy
molar absorptivities, e
spin forbidden, Laporte forbidden (HS d 5) 0.1
spin allowed, Laporte forbidden (Oh) 10
spin allowed, Laporte relaxed (Td) 100
spin allowed, Laporte allowed (CT) 10,000
configuration example ground state allowed excited states #bands Δo
d 1 Oh, d
9 Td Ti(H2O)63+ 2T2
2E 1 E
d 2 Oh, d
8 Td V(H2O)63+ 3T1 (F) 3T2,
3T1(P), 3A2 3 usually ΔE3-1
d 3 Oh, d
7 Td Cr(H2O)63+ 4A2
4T2, 4T1(F), 4T1(P) 3 E1
d 4 Oh, d
6 Td Cr(H2O)62+ 5E 5T2
1 E
d 5 Oh, Td Mn(H2O)6
2+ 6A1 none 0 -
d 6 Oh, d
4 Td Fe(H2O)62+ 5T2
5E 1 E
d 7 Oh, d
3 Td Co(H2O)62+ 4T1(F) 4T2,
4T1(P), 4A2 3 usually ΔE3-1
d 8 Oh, d
2 Td Ni(H2O)62+ 3A2
3T2, 3T1(F), 3T1(P) 3 E1
d 9 Oh, d
1 Td Cu(NH3)62+ 2E 2T2 1 E
O
O
Cr O
O O
O
O
O
Effect of Reduced Symmetry
Cr
H2O
H2O OH2
OH2
OH2
H2O
Oh
D3
Cr(H2O)63+
Cr(C2O4)33–
similar field (both O)
> e; no i.
Cr(en)33+
stronger field (N vs O)
> e; no i.
D3
0
50
100
350 400 450 500 550 600 650 700
l (nm)
e
Cr H2N
H2N N
N
NH2
NH2
H2
H2
Cr
O
O O
O
O
O
Cr
N
N N
N
N
N
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Effect of Reduced Symmetry
0.0
0.2
0.4
0.6
0.8
1.0
400 500 600 700 800
A
l (nm)
Ni(en)32+ (D3)
Ni(H2O)62+ (Oh)
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
400 500 600 700 800
A
l (nm)
CuCl42– (Td)
Cu(H2O)62+ (D4h)
Ni H2O
H2O OH2
OH2
OH2
H2O
Cu
H2O
H2O OH2
OH2
OH2
H2O
Cl
Cu
Cl Cl Cl
Ni H2N
H2N N
N
NH2
NH2
H2
H2
Metal ion g k Ligand f h
Co2+ 9.3 0.24 Br– 0.76 2.3
Co3+ 19.0 0.35 Cl– 0.80 2.0
Cr3+ 14.1 0.21 F– 0.90 0.8
Fe3+ 14.0 0.24 CN– 1.7 2.0
Ir3+ 32 0.3 en 1.28 1.5
Mn2+ 8.5 0.07 H2O 1.00 1.0
Mn4+ 23 0.5 NH3 1.25 1.4
Mo3+ 24 0.15
Ni2+ 8.9 0.12
Pt4+ 36 0.5
Re4+ 35 0.2
Rh3+ 27.0 0.3
V2+ 12.3 0.08
Estimating B′ and D of Octahedral Complexes
Do = fg
B′ = B(1 – hk)
(in 103 cm–1)