  The complete tensor structure of the quark--gluon vertex in Landau gauge is
determined at two kinematical points (`asymmetric' and `symmetric') from
lattice QCD in the quenched approximation. The simulations are carried out at
beta=6.0, using a mean-field improved Sheikholeslami-Wohlert fermion action,
with two quark masses ~ 60 and 115 MeV. We find substantial deviations from the
abelian form at the asymmetric point. The mass dependence is found to be
negligible. At the symmetric point, the form factor related to the
chromomagnetic moment is determined and found to contribute significantly to
the infrared interaction strength.
