title: Molecular geometry as a source of chemical information. 5. Substituent effect on proton transfer in para-substituted phenol complexes with fluoride--a B3LYP/6-311+G study.
abstract: The simplified model system [p-X-PhO...H...F](-), where -X are -NO, -NO(2), -CHO, -H, -CH(3), -OCH(3), and -OH, with various O...F distance was used to simulate the wide range of the H-bond strength. Structural changes due to variation of the substituent as well as the H-bond strength are well monitored by the changes in the aromaticity index HOMA and by two empirical measures of the H-bond strength-the (1)H NMR chemical shift of proton involved and the C-O bond length. Changes in H-bonding strengths and the position of proton transfer while shortening the O...F distance are well described by the Hammett equation.
authors.affiliation: Department of Chemistry, Warsaw University, Pasteura 1, 02-093 Warsaw, Poland.
authors.forename: Tadeusz M
authors.initials: TM
authors.lastname: Krygowski
authors.forename: Halina
authors.initials: H
authors.lastname: Szatyłowicz
authors.forename: Joanna E
authors.initials: JE
authors.lastname: Zachara