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The construction of symmetric states of N particles with angular momentum j=1 is presented. Elliott's result (1958), dealing with the angular momentum content of the symmetric subset of states belonging to the set of states of N particles with angular momentum j=1 is obtained using Racah algebra for the angular momentum coupling. The explicit functional dependence, on the total angular momentum, of the coefficients of fractional parentage (CFP) associated with one, two, three and four removed particles is found for arbitrary values of N. This dependence is expressed through the simple algebraic functions of J and N.

For pt.I see ibid., vol.10, p.2471 (1977). The results on partially aligned groundstates found in pt.I in the two-spin case are extended to the many-spin case by a generalized mean-field theory with a site-dependent axis of quantization. It is found that the corresponding groundstate is partially aligned in regions of the parameter space agreeing qualitatively with the exact two-spin results. For the case of sufficiently symmetrical lattices with isotropic nearest-neighbour interactions, the partially aligned groundstate is degenerate with respect to a one-parameter family of helical spin structures. Such helical states are shown to be unstable in the presence of an infinitesimal external field against conversion to a canted two-sublattice structure.