G. Kamieniarz

Critical Ising lines of the d=2 Ashkin-Teller model

The universal critical point ratio

Exact simulations of quantum rings and characterization of hexanuclear manganese and dodecanuclear nickel cyclic complexes

Q

Static properties of quantum spin S=1 chains: TMNB, TMNC and CsNiF3

is exploited to determine positions of the critical Ising transition lines on the phase diagram of the Ashkin-Teller (AT) model on the square lattice. A leading-order expansion of the ratio

Magnetization-based assessment of correlation energy in canted single-chain magnets

Q

Specific heat of segmented Heisenberg quantum spin chains in (Yb1-xLux)4As3

in the presence of a non-vanishing thermal field is found from finite-size scaling and the corresponding expression is fitted to the accurate perturbative transfer-matrix data calculations for the

Application of Parallel Computing in the Transfer-Matrix Simulations of the Supramolecular Rings

L\times L

Large-scale simulations of the finite-temperature properties of the molecular assemblies Mn6 and Ni12

square clusters with

Finite chain results for the magnetization and specific heat of CsNiF3

L\leq 9

Deterministic Large-Scale Simulations of the Low-Dimensional Magnetic Spin Systems

.

Application of Parallel Computing in the Transfer - Matrix Simulations of the Supramolecules Mn6 and Ni12

A numerical transfer-matrix approach and diagonalization technique exploiting the point-group symmetry are worked out in the framework of quantum statistical mechanics and group theory as exact simulation tools for application to thermodynamical properties of finite rings. They are applied to the isotropic spin models of the high-nuclearity cyclic clusters [Mn(hfac)2NITPh]6 and Ni12(O2CMe)12(chp)12(H2O)6(THF)6. The microscopic parameters of both molecules (J/kB = 350?10?K and J/kB = 8.5?0.5?K, respectively, with g = 2.23?0.01) are then obtained from a fit of the theoretical susceptibility curves to the experimental results.