What is the geometry of the coordination sphere in [Ni(en)2]2+?
[Ni(en)2]2+ (Ni₂+, d8) with 2 bidentate en (4 donor atoms) is square planar, using dsp2 hybridization.
Ref: NCERT Class 12 Chemistry > Chapter 5: Coordination Compounds > Topic: Bonding - Valence Bond Theory and Hybridisation