Two important physical evidences supporting the synergic bonding in non-classical complexes are bond lengths and vibrational spectra. Vibrational spectra is based on the fact that the compression and extension of a bond may be analogous to the behaviour of a spring and obeys Hook's law.
`overline(v)=(1)/(2pic)sqrt((k)/(mu))cm^(-1)`
where, k=force force constant of the bond which is directly proportional to bonnd strength of CO `mu=`reduced mass of ligand
`overline(v)`=stretching frequency of the CO bond
c=velocity of light
Q. In `Mn_(2)(CO)_(10)` carbonyl complex, the d-orbital of Mn-atom which can not be involved in synergic bonding betwee Mn and CO ligands:

Options

A. `d_(xz)`
B. `d_(xy)`
C. `d_(yz)`
D. none of these

Answer

B

Explanation

As `d_(xy)` forms `delta`-bondin `Mn_(2)(CO)_(10)`