|
Publications
|
|
||
| |
||
|
||
| ||
|
|
"A Generalized Resonance Model for Substituted 1,4-Benzoquinones" M. NonellaJ. Phys. Chem. 103A, 1999, 7069-7075 Abstract: Resonance effects are known to affect vibrational spectra and electrochemical properties of substituted quinones. On the basis of the results of density functional calculations on several singly substituted 1,4-benzoquinones we propose an extended resonance model which can account for the most prominent substituent effects onto the force constants of carbon-carbon and carbon-oxygen bonds. The calculations show that the two proposed resonance mechanisms are closely coupled. This interplay of the two effects renders a quantitative prediction of force constants of substituted 1,4-benzoquinone difficult. We nevertheless can give some simple rules which in many cases can give a good estimate for expected force constant changes upon substitution of 1,4-benzoquinone. BMO authors (in alphabetic order): Marco Nonella |