Partition function zeros and magnetization plateaus of the spin-1 Ising–Heisenberg diamond chain

We study the properties of the generalized spin-1 Ising–Heisenberg model on a diamond chain, which can be considered as a theoretical model for the homometallic magnetic complex [Ni3(C4H2O4)2−(µ3−OH)2(H2O)4]n ·(2H2O)n. The model possesses a large variety of ground-state phases due to the presence of biquadratic and single-ion anisotropy parameters. Magnetization and quadrupole moment plateaus are observed at one- and two-thirds of the saturation value. The distributions of Yang–Lee and Fisher zeros are studied numerically for a variety of values of the model parameters. The usual value σ = − 1 2 alongside an unusual value σ = − 2 3 is determined for the Yang–Lee edge singularity exponents.