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We consider the one dimensional, periodic spin chain with $N$ sites, similarto the one studied by Haldane \cite{hal}, however in the opposite limit of verylarge anisotropy and small nearest neighbour, anti-ferromagnetic exchangecoupling between the spins, which are of large magnitude $s$. For a chain withan even number of sites we show that actually the ground state is nondegenerate and given by a superposition of the two N\'eel states, due toquantum spin tunnelling. With an odd number of sites, the N\'eel state mustnecessarily contain a soliton. The position of the soliton is arbitrary thusthe ground state is $N$-fold degenerate. This set of states reorganizes into aband. We show that this occurs at order $2s$ in perturbation theory. The groundstate is non-degenerate for integer spin, but degenerate for half-odd integerspin as is required by Kramer's theorem \cite{kram}.

Haldane-like antiferromagnetic spin chain in the large anisotropy limit