Boron nuclear quadrupole coupling in <i>o</i>- and <i>m</i>-carborane (B1C2H12)

Abstract

The 11B nuclear quadrupole coupling in the title compounds is reported. The experimental technique applied was double resonance with level crossing. The values for (e2qQ/h)(1+η2/3)1/2 are (in MHz, errors of last digits and assignments in brackets): o-carborane: 1.10(6) (B8,B10) (tentative), 1.22(6) (B9,B12), 1.60(4) (B4,B5,B7,B11), 1.86(4) (B3,B6); m-carborane: 1.22(4) (B9,B10), 1.56(12) (all other borons, unresolved).