Question

The types of bond that are formed by dz2 and s orbital on each molecular axis

Answer 1

Sigma bond

Answer 2

An $s$ orbital is spherical and can only form sigma ($\sigma$) bonds through head-on overlap. It cannot form pi ($\pi$) or delta ($\delta$) bonds due to its lack of nodal planes. The $d_{z^2}$ orbital has lobes along the z-axis and a doughnut in the xy-plane. When the internuclear axis is the z-axis, the $s$ orbital can undergo head-on overlap with the z-lobes of the $d_{z^2}$ orbital, forming a $\sigma$ bond. If the internuclear axis is the x or y axis, the $s$ orbital interacts with the doughnut of the $d_{z^2}$ orbital, leading to destructive interference or non-bonding interaction because of phase differences and unsuitable symmetry for sigma bonding along those axes. Therefore, only sigma bonds are formed.