Critical analysis of the through-space transmission of NMR J(FH) spin-spin coupling constants.

R. H. CONTRERAS, C. F. TORMENA, L. C. DUCATI

INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY

JOHN WILEY & SONS INC

Lugar: New York; Año: 2012 vol. 112 p. 3158 - 3163

0020-7608

NMR JFH coupling constants transmitted through space areknown to show several unusual peculiarities. The main threeare (a) in many cases their experimental values are reported tobe positive and in others, negative; (b) theoretical values showthat in some cases they are substantially contributed not onlyfrom the Fermi contact (FC) term but also from theparamagnetic spin orbit (PSO) term, and their respective signscould be either like or unlike; (c) in many cases it can hardly beexpected that the corresponding FAH proximate interactionscould be considered a ‘‘hydrogen bond,’’ whereas in other casesit is evident that they are. For discussing points (a) and (b),characteristics of both the FC and PSO terms are discussedperforming qualitative analyses based on their expressionsgiven in terms of the polarization propagator formalism. Point(c) is discussed in terms of the well-known Bader’s QTAIMmethod as well as recalling the known relationship betweenthe transmissions of the Fermi hole and of the FC interaction ofspin–spin coupling constants. VC 2012 Wiley Periodicals, Inc.