ISSN:
1057-9257
Keywords:
quantum chemical semiempirical calculations
;
m-nitrophenol
;
polymorphic forms
;
hyperpolarisabilities
;
electron affinities
;
electronic transitions
;
spin densities
;
hydrogen bonding
;
proton transfer
;
paramagnetic species
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Electrical Engineering, Measurement and Control Technology
,
Physics
Notes:
Energy differences between m-nitrophenol (mNP) molecules in the gas phase and in two crystalline polymorphic forms - the optically non-linear orthorhombic and the centro-symmetric monoclinic form - have been found by the semiempirical all-valence modified INDO method. The calculations were performed for neutral molecules and for possible ions as well as for deprotonated molecules in the three phases. The values obtained for electron affinities, hyperpolarisabilities, electronic transition energies and spin desities on atoms in open-shell structures indicate that paramagnetic species are most favoured in the orthorhombic polymorph. This tendency corroborates our ESR results on the generation of unpaired spins by near-infrared excitation.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
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