Determination of the 51V and 93Nb quadrupole coupling tensors in two eight-coordinated complexes

The quadrupole coupling tensors of 51V and 93Mb in tetrakis(dithiobenzoato)Mo(IV) and tetrakis(diethyldithiocarbamato)Ti(lV) have been obtained from EPR measurements. No similar measurements have been reported previously for the niobium ion. The experimental results suggest the value of the electric quadrupole moment to be -0.35 barn.