Critical behavior of frustrated spin systems with nonplanar orderings

The critical behavior of frustrated spin systems with nonplanar orderings is analyzed by a six-loop study in fixed dimension of an effective O$(N)\times$O$(M)$ Landau-Ginzburg-Wilson Hamiltonian. For this purpose the large-order behavior of the field theoretical expansion is determined. No stable fixed point is found in the physically interesting case of $M=N=3$, suggesting a first-order transition in this system. The large $N$ behavior is analyzed for $M=3,4,5$ and the line $N_c(d=3,M)$ which limits the region of second-order phase transition is computed.