. The 1-D Heisenberg and Ising models:

1. The XXZ model with arbitrary value of spin, with external magnetic field parallel to the z-axis;

1.1. HFE for spin-S , up to order ß6 : W_Quant_XXZ_beta6.txt

2. The XYZ model with normalized arbitrary spin, with external magnetic field parallel to the z-axis
2.1. HFE of the quantum version of the model, up to order β5 : W_Quant_XYZ_beta5.txt
2.2. HFE of the classical version of the model, up to order β12 : W_Class_XYZ_beta12.txt

3.The Ising model for arbitrary normalized spin, with magnetic field in the yz-plane
3.1. HFE of the quantum version of the model, up to order β7 : W_Quant_TIsing_beta_7.txt
3.2. HFE of the classical version of the model, up to order β16 : W_Class_TIsing_beta_16.txt

4. The Ising model with single-ion anisotropy term for arbitrary normalized spin, in the presence of a longitudinal magnetic field
4.1. HFE of the quantum version of the model, up to order β17 : W_Quant_LongIsing_Sz2_beta_17.txt
4.2. HFE of the classical version of the model, up to order β17: W_Class_LongIsing_Sz2_beta_17.txt

5. The staggered Ising model for arbitrary normalized spin, in the presence of a longitudinal magnetic field
5.1. HFE of the quantum version of the model, up to order β17 : W_Quant_IsingStag_beta_17.txt
5.2. HFE of the classical version of the model, up to order β17: W_Class_LongIsing_Sz2_beta_17.txt