Theory of molecular optoelectronics. X: Calculations for MBANP and NMBA
Article first published online: 14 SEP 2004
Copyright © 1992 John Wiley & Sons Ltd.
Advanced Materials for Optics and Electronics
Volume 1, Issue 2, pages 65–71, April 1992
How to Cite
Munn, R. W. and Smith, S. P. B. (1992), Theory of molecular optoelectronics. X: Calculations for MBANP and NMBA. Adv. Mater. Opt. Electron., 1: 65–71. doi: 10.1002/amo.860010204
- Issue published online: 14 SEP 2004
- Article first published online: 14 SEP 2004
- Manuscript Revised: 17 JAN 1992
- Manuscript Received: 18 NOV 1991
- Non-linear optics;
- Molecular crystals;
- Local field;
- Dipole interactions;
Components of the crystal quadratic susceptibility tensor x(2) for second-harmonic generation are calculated for the title compounds 2-(α-methyl benzylamino)-5-nitropyridine (MBANP) and 4-nitro-4'-methyl(benzylidene aniline) (NMBA). Input data are the crystal structure and refractive indices and CNDO hyperpolarizabilities. The calculations also yield effective polarisabilities and local electric fields. Susceptibility components reach 66 pm V−1 in MBANP and 27 pm V−1 in NMBA in the crystal axes; agreement with experiment is poor for MBANP but satisfactory for NMBA. These features seem to reflect the better defined charge transfer axis in NMBA. Screened dipole–dipole interactions calculated from CNDO dipole moments stabilise MBANP by 70 kJ mol−1 and NMBA by 20 kJ mol−1 and imply permanent electric fields of a few GV m−1.