Abstract: Aunitary group treatment for the strong-field model is discussed in this paper.All the formulas necessary for calculation of an octahedral symmetry field are geven and programed in IBM PC/ XT.The program has low storage requirement and reasonable speed.Energy parameters and eigen-functions obtained by fitting spectroscopy experiments are satisfactory, which will be used to calculate magnetic and other properties of complex compounds.

Key words: Ligand field calculation, Unitary group method, Microcomputer program