The electronic structure of the metastable compound (a = 3.399 Å, c = 5.911 Å, space group ) was calculated with and without spin polarization using the LSW method. The energy is 0.29 eV/mol lower for the spin-polarized calculation. The total magnetic moment of on Cr consists of in spin-up and in spin-down states; the total number of 3d electrons on Cr is 4.12, much greater than expected for Cr(IV) . The Cr 3d-based bands overlap the selenium 4p-based valence band which implies strong covalency of the Cr - Se bonding. At the Fermi level there are electrons and holes with Cr 3d character, and holes with Se 4p character. The results clearly indicate the reduction of the cations and the presence of holes in the Se 4p valence band. is a magnetic metal. Similar calculations for showed a very small energy difference between the magnetic and non-magnetic states, indicating that is a non-magnetic metal.