The electronic absorption spectrum of the title crystal of the clathrate co
mpound of [Ni(en)(2)(NCS)(2)]. C6H6 has been measured. The experimental res
ults are discussed quantitatively with ligand field theory(LFT) and the rad
ial wave function of non-free nickel(II) ion. The calculation values coinci
de well with the experimental results. In particular, they provide signific
ant correlation between the electronic absorption spectrum and the crystal
structure of the compound.