PARAMAGNETIC CLOSED-SHELL MOLECULES - THE ISOELECTRONIC SERIES CH+, BH AND BEH-

Coupled Hartree-Fock calculations predict CH+, like its isoelectronic analogue BH, to be paramagnetic. The calculated magnetizability has components chi-parellel-to(CH+) = -1.44 and chi-perpendicular-to(CH+) = +10.54 a.u. with a mean value chiBAR(CH+) = +6.55 a.u. (5.17 x 10(-28) JT-2). Predicted nuclear shieldings are sigmaBAR(C) = -1250 ppm and sigmaBAR(H) = +34.1 ppm. The isolated BeH- anion is predicted to lie on the diamagnetic/paramagnetic borderline, but when placed in a crystal lattice is likely to be weakly diamagnetic.