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 which of the following ligand, sigma-bond order does not change during synergic bonding in their respective complexes:

Two important physical evidences supporting the synergic bonding in no

1.	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 which of the following ligand, sigma-bond order does not change during synergic bonding in their respective complexes:
Answer» CO `N_(2)` `CH_(2)=CH_(2)` `PE t_(3)` SOLUTION :As `PE t_(3) ` accepts `M overset(PI)toL` back bonding into non-axial d-ORBITAL of phosphorus annd it FORMS `Moverset(pi)toL` bond using its non-bonding molecular orbital.