NH 3 and PH 3 molecular quadrupole moments and the signs of molecular g-values

Abstract

Molecular Zeeman effect data for NH 3 and PH 3 was reviewed and reanalyzed to obtain molecular quadrupole moments. Since the signs of molecular g-values were not directly measured, molecular quadrupole moments were also calculated using ab initio SCF programs to remove ambiguities in the signs of g-values. For NH 3, Q cc (measured) = −3.4(4) buckingham and Q cc (calculated) = −2.8 buckingham. For PH 3, Q cc (measured) = −2.3(12) buckingham and Q cc (calculated) = −2.4 buckingham. These values support positive g-values for NH 3 ( g aa = g bb =0.568(2), g cc =0.500(2)), and for PH 3 g aa = g bb =−0.325(9), and g cc =0.011(1).