24737-19-7Relevant academic research and scientific papers
Nuclear spin-spin coupling via nonbonded interactions. 8. The distance dependence of through-space fluorine-Fluorine coupling
Mallory, Frank B.,Mallory, Clelia W.,Butler, Kelly E.,Lewis, Mary Beth,Xia, Angell Qian,Luzik Jr., Eddie D.,Fredenburgh, Laura E.,Ramanjulu, Mercy M.,Van, Que N.,Francl, Michelle M.,Freed, Dana A.,Wray, Chandra C.,Hann, Christine,Nerz-Stormes, Maryellen,Carroll, Patrick J.,Chirlian, Lisa E.
, p. 4108 - 4116 (2007/10/03)
The 19F19F nuclear spin-spin coupling constants J(FF) for a set of eighteen compounds related structurally to 1,8-difluoronaphthalene were measured by 19F NMR spectroscopy. The FF distances d(FF) in these compounds were determined by ab initio 3-21G* molecular orbital calculations. Consistent with the lone-pair overlap theory of the origins of through-space 19F19F coupling, an exponential relationship is found between J(FF) and d(FF) (regression coefficient r2 = 0.991), and a linear relationship is found between J(FF) and the extent of the overlap interaction between the in- plane fluorine 2p lone-pair orbitals (regression coefficient r2 = 0.993). The magnitudes of these lone-pair interactions were estimated from molecular orbital energies obtained by ab initio 6-31G* calculations for a model consisting of a pair of HF molecules separated by various distances.
