Susceptibility Behaviour of CuGeO$\text{}_{3}$: Comparison between Experiment and the Quantum Transfer Matrix Approach

Thermodynamical properties of one-dimensional S=1/2 Heisenberg model with dimerized nearest- and uniform next-nearest-neighbour interactions are studied by the numerically exact quantum transfer matrix method and the results are applied to CuGeO$\text{}_{3}$. Suzuki-Trotter formula is used to obtain a classical system with spin σ=3/2 and effective interactions between nearest-neigbours only. Magnetic susceptibility curve is calculated and compared with new experimental results performed in a wide temperature range, revealing the presence of frustration in the model proposed for CuGeO$\text{}_{3}$.