Question

Which of the following linear combinations of atomic orbitals will lead to the formation of molecular orbitals in homonuclear diatomic molecules (internuclear axis in z-direction)?
(1) \( 2p_z \) and \( 2p_x \) 
(2) \( 2s \) and \( 2p_x \) 
(3) \( 3d_{xy} \) and \( 3d_{x^2-y^2} \) 
(4) \( 2s \) and \( 2p_z \) 
(5) \( 2p_z \) and \( 3d_{x^2-y^2} \) 
 

• A. E only
• B. A and B only
• C. D only
• D. C and D only

Hint:

When combining orbitals for molecular orbital formation along the internuclear axis, ensure that the orbitals have components along the axis. For the z-axis, \( 2p_z \) and \( 2s \) orbitals are suitable combinations.

Answer 1

The Correct Option is C

For molecular orbital formation along the z-direction, the atomic orbitals must have components along the z-axis. 
The correct combination involves: - \( 2s \) and \( 2p_z \), both of which have components along the z-axis, and can combine effectively to form bonding and antibonding molecular orbitals. 
Thus, the correct answer is \( \boxed{(3) D Only} \).