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Title: Structural study of 1- and 2-naphthol: new insights into the non-covalent H–H interaction in cis -1-naphthol
Previous microwave studies of naphthol monomers were supplemented by measuring spectra of all 13 C mono-substituted isotopologues of the cis - and trans -conformers of 1-naphthol and 2-naphthol in their natural abundances. The resulting data were utilized to determine substitution structures and so-called semi-experimental effective structures. Results from electronic structure calculations show that the OH group of cis -1-naphthol points ≈6° out of plane, which is consistent with the inertial defect data of cis - and trans -1-naphthol. The non-planarity of cis -1-naphthol is a result of a close-contact H-atom–H-atom interaction. This type of H–H interaction has been the subject of much controversy in the past and we provide here an in-depth theoretical analysis of it. The naphthol system is particularly well-suited for such analysis as it provides internal standards with its four different isomers. The methods used include quantum theory of atoms in molecules, non-covalent interactions, independent gradient model, local vibrational mode, charge model 5, and natural bond orbital analyses. We demonstrate that the close-contact H–H interaction is neither a purely attractive nor repulsive interaction, but rather a mixture of the two.  more » « less
Award ID(s):
1464906
PAR ID:
10342517
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Physical Chemistry Chemical Physics
Volume:
24
Issue:
6
ISSN:
1463-9076
Page Range / eLocation ID:
3722 to 3732
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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