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 resu
lts are discussed quantitatively with ligand field theory(LFT) and the radi
al wave function of non-free nickel(II) ion. The calculation value coincide
s well with the experimental results. In particularly, it provides signific
ant correlation between the electronic absorption spectrum and the crystal
structure of the compound.