Question

Explain the geometry of [Cu(NH₃)₄]²⁺ on the basis of hybridisation [ At. No. Cu = 29 ]. 

Answer 1

1. The oxidation state of Cu in [Cu(NH₃)₄]²⁺ is + 2. The electronic configuration of Cu²⁺ is 3d⁹4s⁰.
2. dsp² hybridisation of one d, one s and two p orbitals result in square planar geometry.
3. Coordinate bonds are formed by overlap of metal dsp2 hybrid orbitals.
   
4. Due to presence of one unpaired electron, [ Cu(NH₃)₄ ]²⁺ is paramagnetic. The magnetic moment, μ is 1.73 B.M.