Stabilisation energy of octahedral complex with `d^(7)` configuration
(A) `-1.8 Delta_(0)` with one unpaired electron
(B) `1.8 Delta_(0)` with three unpaired electrons
(C) `-0.8 Delta_(0)` with one unpaired electron
(D) `0.8 Delta_(0)` with three unpaired electrons

Options

A. A and D
B. A and B
C. C and D
D. B and C

Answer

1

Explanation

For strong field ligands -
`CFSE = (-6xx0.4 - 1xx0.6) = -1.8Delta_(0)`
one unpaired electron
For weak field ligands
`CFSE = (-5xx0.4 - 2xx0.6) = -0.8Delta_(0)`
three unpaired electrons