Moments, Charges, Bond Orders, Atoms-in-Molecules......... 7.3.4 Properties Arising from Electron Distribution – Dipole
Moments, Charges, Bond Orders, Atoms-in-Molecules
The theory behind calculating dipole moments, charges, and bond orders, and using
atoms-in-molecules analyses, was outlined in Section 5.5.4; here the results of
applying DFT calculations to these will be presented.
7.3.4.1 Dipole Moments
Hehre [ 67 ] and Hehre and Lou [ 68 ] have provided quite extensive compilations of
calculated dipole moments. These confirm that Hartree–Fock dipole moments tend
80
60
40
20
0
TR_TNTRNS
TR_TNTRNS
0
26
52
78
4000
4000
3000
3500 3000
2000
2500 2000
1000
1500 1000 500
Benzene^3091
Experimental
B3LYP / 6-31G*
MP2 / 6-31G*
3050
1480
1040
674
692
1083
1540
689
1533 1071
3201
3239
FREQ_VAL
FREQ_VAL
0
37
73
1.1e+002
4000 3500 3000 2500 2000 1500 1000 500
Fig. 7.5 Experimental (gas phase), DFT (B3LYP/6-31G) and ab initio (MP2(fc)/6-31G)
calculated IR spectra of benzene
7.3 Applications of Density Functional Theory 487