Values of f and g for estimating Δo (10 Dqo), and of h and k for estimating β
Ligand | f | h | Metal ion | g, cm-1 | k |
Br- | 0.72 | 2.3 | Mn2+ | 8,000 | 0.07 |
-SCN- | 0.75 | - | Ni2+ | 8,700 | 0.12 |
Cl- | 0.78 | 2.0 | Co2+ | 9,000 | 0.09 |
OPCl3 | 0.82 | - | V2+ | 12,000 | 0.08 |
N3- | 0.83 | - | Fe3+ | 14,000 | 0.24 |
F- | 0.9 | 0.8 | Cu3+ | 15,700 | - |
OSMe3- | 0.91 | - | Cr3+ | 17,400 | 0.21 |
OCMe2 | 0.92 | 1.2 | Co3+ | 18,200 | 0.35 |
EtOH | 0.97 | - | Ru2+ | 20,000 | - |
Me2NCHO | 0.98 | - | Ag3+ | 20,400 | - |
C2O42- | 0.99 | 1.5 | Ni4+ | 22,000 | - |
H2O | 1.00 | 1.0 | Mn4+ | 24,000 | 0.5 |
SC(NH2)2 | 1.01 | - | Mo3+ | 24,600 | 0.15 |
-NCS- | 1.02 | - | Rh3+ | 27,000 | 0.30 |
-NCSe- | 1.03 | - | Mn2+ | 8,000 | 0.07 |
-NH2CH2CO2-- | 1.18 | - | Tc4+ | 31,000 | - |
CH3CN | 1.22 | - | Ir3+ | 8,000 | 0.3 |
C5H5 | 1.23 | - | Pt4+ | 36,000 | 0.5 |
NH3 | 1.25 | 1.4 | Fe2+ | 8,500 | 0.08 |
en | 1.28 | 1.5 | - | - | - |
-SO32- | 1.2 | - | - | - | - |
diars | 1.33 | - | - | - | - |
bipy | 1.33 | - | - | - | - |
-NO2- | 1.4 | - | - | - | - |
CN- | 1.7 | 2.0 | - | - | - |
From C. K. Jorgensen, "Modern Aspects of Ligand Field Theory," American Elsevier, NY (1971) pp 347-348 and C. K. Jorgensen, "Absorption Spectra and Chemical Bonding in Complexes," Pergamon, Oxford (1962) p. 113.
The reduced Racah parameter, β may be calculated by the equation below:
β = 1 - hk
Once β has been calculated it can be used to calculate Bcomplex using the formula below:
Bcomplex = βBfree ion
A table of Bfree ion values appears below:
Free ion values of B for transition metal ions (in cm-1)
Metal | M2+ | M3+ |
Ti | 695 | - |
V | 755 | 861 |
Cr | 810 | 918 |
Mn | 860 | 965 |
Fe | 917 | 1015 |
Co | 971 | 1065 |
Ni | 1030 | 1115 |
From William L. Jolly, "Modern Inorganic Chemistry," McGraw-Hill Book Co., NY (1989) p 411.