First nickel(II) complexes containing tetrahedral NiO2S2 cores. The molecular structures of Ni[(OPPh2)(SPR2)N]2 (R=Ph, Me)

First nickel(II) complexes containing tetrahedral NiO2S2 cores. The molecular structures of Ni[(OPPh2)(SPR2)N]2 (R=Ph, Me)