Transition metal species are known that contain multiple metal-carbon bonds, for example, M=CH2. Describe how the π portion of the M=C bond would be formed using a pure d orbital on M and in what plane the protons on the CH2 group would lie. (A d orbital is employed because it is lower energy and because it extends out toward the carbon atom, which gives rise to better overlap with the orbital on C.) What hybrid orbitals could be employed to form the s portion of the M=C bond?
The Attempt at a Solution
For the first part of the problem, I think you can use a dxz orbital on M when the carbon has a pz orbital. But what do they mean by what plane the protons on the CH2 group would lie? Also, advice on the last part of the question would be appreciated...