Abstract: A simple and convenient strong field scheme for treating the absorption spectra of the complex ions with lower symmetry groups is suggested. The complete energy matrices of terms corresponding to the irreducible representations of C_2hpoint group for d⁵system are derived.The complicated electronic absorption spectrum of Mn²⁺in MnCl₂·2H₂O is analyzed and explained by means of these matrices and by considering the vibronic coupling and double electron excitation.