  We study the physical processes that affect the alignment of grains subject
to radiative torques (RATs). To describe the action of RATs, we use the
analytical model (AMO) of RATs introduced in Paper I. We focus our discussion
on the alignment by anisotropic radiation flux with respect to magnetic field,
which defines the axis of grain Larmor precession. Such an alignment does not
invoke paramagnetic dissipation (i.e. Davis-Greenstein mechanism), but,
nevertheless, grains tend to be aligned with long axes perpendicular to the
magnetic field. When we account for thermal fluctuations within grain material,
we show that for grains, which are characterized by a triaxial ellipsoid of
inertia, the zero-$J$ attractor point obtained in our earlier study develops
into a low-$J$ attractor point. We study effects of stochastic gaseous
bombardment and show that gaseous bombardment can drive grains from low-$J$ to
high-$J$ attractor points in cases when the high-$J$ attractor points are
present. As the alignment of grain axes with respect to angular momentum is
higher for higher values of $J$, counter-intuitively, gaseous bombardment can
increase the degree of grain alignment in respect to the magnetic field. We
also study the effects of torques induced by H$_2$ formation and show that they
can change the value of angular momentum at high-$J$ attractor point, but
marginally affect the value of angular momentum at low-$J$ attractor points. We
compare the AMO results with those obtained using the direct numerical
calculations of RATs acting upon irregular grains and validate the use of the
AMO for realistic situations of RAT alignment.
