NMR 3J(C1, H3) couplings in 1-X-bicyclo[1.1.1]pentanes. FPT-DFT and NBO studies of hyperconjugative interactions and heavy atom substituent effects. - Verónica Barone; Juan E. Peralta; Rubén H. Contreras (J. Comput. Chem., 2001)