TY - JOUR
T1 - Vibrational versus electronic first hyperpolarizabilities of π-conjugated organic molecules
T2 - An ab initio Hartree-Fock investigation upon the effects of the nature of the linker
AU - Champagne, Benoît
AU - Kirtman, Bernard
PY - 1999/7/1
Y1 - 1999/7/1
N2 - Ab initio RHF calculations have been used to study the relative variation of βe and βv in D/A (NH2/NO2) substituted π-conjugated compounds as a function of the specific nature, length, and charge of the linker. For the vibrational property we have separated off the contribution due low-frequency (ω≤100 cm-1) modes, which have long response times and are associated primarily with torsional motions. For all cases considered the βv; 100(0)/βe(0) ratio lies in the range 1.35-6.58. In our systematic comparisons we have found that increases in βe are most often accompanied by increases in βv. Similar behavior has also been obtained previously for a series of mono- and di-substituted benzenes. However, there are counter-examples as well: when the conjugation is broken by inserting an sp3 defect, when changing the nature of the aromatic rings in stilbene-like linkers and, more importantly, upon doping α,ω-nitro,amino all-trans polyene chains.
AB - Ab initio RHF calculations have been used to study the relative variation of βe and βv in D/A (NH2/NO2) substituted π-conjugated compounds as a function of the specific nature, length, and charge of the linker. For the vibrational property we have separated off the contribution due low-frequency (ω≤100 cm-1) modes, which have long response times and are associated primarily with torsional motions. For all cases considered the βv; 100(0)/βe(0) ratio lies in the range 1.35-6.58. In our systematic comparisons we have found that increases in βe are most often accompanied by increases in βv. Similar behavior has also been obtained previously for a series of mono- and di-substituted benzenes. However, there are counter-examples as well: when the conjugation is broken by inserting an sp3 defect, when changing the nature of the aromatic rings in stilbene-like linkers and, more importantly, upon doping α,ω-nitro,amino all-trans polyene chains.
UR - http://www.scopus.com/inward/record.url?scp=0033411401&partnerID=8YFLogxK
M3 - Article
AN - SCOPUS:0033411401
SN - 0009-2614
VL - 245
SP - 213
EP - 226
JO - Chemical Physics Letters
JF - Chemical Physics Letters
IS - 1-3
ER -