Figure 3. Schematic molecular orbital diagram for the CSCu, unit. Symmetry labels correspond to idealized C,,, symmetry. nonbonding (or slightly antibonding, to the extent that the copper orbitals overlap). Inclusion of the sulfur d,,-,, orbital might stabilize the b, orbital slightly, but would provide no additional bonding electrons. The bond lengths indicate that this sixcenter, eight-electron system is tightly bound.
