According to MOT, two atomic orbitals overlap resulting in the formation of molecular orbital formed. Number of atomic orbitals overlapping together is equal to the molecule orbital formed. The two atomic orbital thus formed by LCAO (linear combination of atomic orbital) in the phase or in the different phase are known as bonding and antibonding molecular orbitals respectively. The energy of bonding molecular orbital is lower than that of the pure atomic orbitals by an amount `Delta`. This known as the stabilization energy. The enerby of antibonding molecular orbital in increased by `Delta'` (destabilisation energy).
Q. If x-axis is the molecular axis, then `pi`-moleulcar orbitals are formed by the overlap of :

Options

A. `S+p_(x)`
B. `p_(x) +p_(y)`
C. `P_(z) +p_(z)`
D. `p_(x)+p_(x)`

Explanation

To solve the question regarding the formation of π-molecular orbitals when the x-axis is the molecular axis, we need to analyze the conditions under which π-molecular orbitals are formed. Here’s a step-by-step solution:

### Step 1: Understand the Formation of Molecular Orbitals
Molecular orbitals are formed through the linear combination of atomic orbitals (LCAO). There are two types of molecular orbitals: bonding and antibonding.

### Step 2: Identify the Type of Overlap
For π-molecular orbitals to form, the atomic orbitals must overlap sidewise. This is different from σ-molecular orbitals, which are formed by head-on overlap of atomic orbitals.

### Step 3: Define the Molecular Axis
In this case, the x-axis is defined as the molecular axis. We need to determine which atomic orbitals can overlap sidewise along this axis.

### Step 4: Analyze the Overlapping Atomic Orbitals
The atomic orbitals that can participate in sidewise overlap are the p orbitals. Specifically, we can consider the pz orbitals, which are oriented perpendicular to the molecular axis (x-axis).

### Step 5: Determine the Correct Overlap
When two pz orbitals from different atoms overlap sidewise, they can form π-bonding and π-antibonding molecular orbitals. This is because the lobes of the pz orbitals can align in such a way that they can overlap effectively.

### Step 6: Conclusion
Thus, the correct answer is that π-molecular orbitals are formed by the sidewise overlap of pz orbitals.

### Final Answer:
**π-molecular orbitals are formed by the overlap of pz orbitals.**

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