Our objective is to obtain the thermodynamics of low-dimensional systems in the regime of high-temperatures. Among the systems we have been studying are the Ising- and Heinsenberg-like one-dimensional spin systems, which describe several materials, including the “single

magnetic molecule” and the “single magnetic chain”, an the strongly correlated systems. Models of Quantum Field Theory such as Thirring and Gross-Neveu models are included in the low-dimensional systems on which we are interested. The method we apply to the calculation of thermodynamic properties of one-dimensional systems in the thermodynamic limit can be equally applied to classical and quantum systems, either fermionic of bosonic, provided that they are homogeneous and satisfy spatial periodic conditions.