Abstract
The magnetization—versus—magnetic-field curve of the one-dimensional chain at T=0 is discussed. Also, the corresponding pV diagram of the quantum lattice gas (q.l.g.) is discussed. The ground-state wave function for the case Δ>1, in a q.l.g. of a finite number of particles on an infinite lattice is analyzed in detail, giving the "surface energy" near the ends. In the Appendix some general properties of the q.l.g. in one, two, or three dimensions are given.