Anisotropies of the Hamiltonian and the Wave Function: Inversion Phenomena in Quantum Spin Chains

We investigate the inversion phenomenon between the XXZ anisotropies of the Hamiltonian and the wave function in quantum spin chains, mainly focusing on the S=1/2 trimerized XXZ model with the next-nearest-neighbor interactions. We have obtained the ground-state phase diagram by use of the degenerate perturbation theory and the level spectroscopy analysis of the numerical data calculated by the Lanczos method. In some parameter regions, the spin-fluid is realized for the Ising-like anisotropy, and the Neel state for the XY-like anisotropy, against the ordinary situation.