Subject: Inorganic Chemistry · Chapter: Coordination Chemistry · Topic: Coordination Chemistry – General · Exam: NET JUNE 2014 · Marks: 2 · Difficulty: Medium
$\mathrm{NiBr}_{2}$ reacts with $(\mathrm{Et})\left(\mathrm{Ph}_{2}\right) \mathrm{P}$ at $-78^{\circ} \mathrm{C}$ in $\mathrm{CS}_{2}$ to give red compound ' A ', which upon standing at room temperature turns green to give compound, 'B' of the same formula. The measured magnetic moments of ' A ' and ' B ' are 0.0 and 3.2 BM, respectively. The geometries of ' A ' and ' B ' are