CNDO/S calculations of magnetic circular dichroism of some mono-substituted benzenes using the complete angular momentum operator

A spectroscopic and structural characterization of the inclusion complexes of p-dimethylaminobenzonitrile with cyclodextrins

“…In the present work the energies and electric dipole moments of the DMABN electronic transitions were calculated using the ZINDO/S program included in the Hyperchem package, with geometries optimized at the MM+ level, whereas the relevant magnetic moments were computed within the complete angular momentum operator framework. 24 The computation of the potential energies of 1:1, 2:1 and 2:2 CD:DMABN complexes was based on Allinger's MM3-92 force field applying a block diagonal matrix minimization method. 25 The fully minimized reference structures of aand b-CD were derived from crystallographic data.…”

On the magnetic circular dichroism of benzene. A density-functional study

“…13,14 The MCD spectroscopy thus tremendously facilitated the absorption studies aimed at the assignment of electronic transitions, as confirmed by subsequent computational works. 4,[15][16][17][18][19] A rich vibrational substructure of some electronic bands 13,14,20 appears to be a common feature of similar aromatic systems. 21 Early assignments of benzene electronic transitions were based on simplified models 4,15 that failed to explain some spectral features.…”

“…25 Yet for computational modeling to be feasible it is desirable to investigate computationally less demanding methods. Semiempirical models such as CNDO (complete neglect of differential overlap) cannot be readily used to describe the Rydberg states, 15 but the Rydberg parameters were incorporated into the Zerner's INDO/S (spectral extension of the intermediate neglect of differential overlap) method. 26 Nowadays, time-dependent density functional theory (TDDFT) represents a more reasonable compromise in computational speed and accuracy, as shown earlier for benzene and its transition energies.…”

Circular dichroic constrained structure optimization of homoalanine peptides

“…This method is adopted in the present case for the electric moments and energies of the two lowest excited states of alanine. 35 However, the magnetic properties and the intrinsic rotational strength of the residues are calculated quantum mechanically within the method of the complete angular momentum operator 36 adopting CNDO/S wave functions.…”