Question

Suppose that a methane molecule became distorted to (a) C_3v symmetry by the lengthening of one bond, (b) C_2v symmetry, by a kind of
scissors action in which one bond angle opened and another closed slightly. Would more d orbitals on the carbon become available for bonding?

Answer 1

First, let me remind you that the carbon atom has the ground state electronic configuration 1S2 2S2 2P2. And the shell no. 2 that is the 'N' shell doesn't have d orbitals as the total subshell available in it are the S and P subshell.

So by distorting the structure of methane from spherical to C3v and then to C2v symmetry we can only change the bond length or/and bond angle, d orbitals can't take part in bonding.