Which one or more among the following involve (s) (pi -dpi) bonding ? .

Options

A. `(SiH_(3))_(3)N:`
B. `(CH_(3))_(3)N:`
C. `:overset(Θ)C CI_(3)`
D. `:overset(Θ)CF_(3)`

Explanation

To determine which of the given compounds involve p-pi d-pi bonding, we need to analyze each option based on the presence of vacant d orbitals in the atom that can accept the lone pair of electrons. Here’s a step-by-step solution:

### Step 1: Understand p-pi d-pi Bonding
p-pi d-pi bonding occurs when a p orbital from one atom overlaps with a vacant d orbital from another atom to form a bond. For this to happen, the atom receiving the lone pair must have vacant d orbitals.

### Step 2: Analyze Each Option

**Option 1: SiH3-Nitrogen**
- Nitrogen has a lone pair of electrons.
- Silicon has the electronic configuration: 1s² 2s² 2p⁶ 3s² 3p² 3d⁰.
- Silicon has vacant d orbitals (3d), so it can accept the lone pair from nitrogen.
- **Conclusion**: p-pi d-pi bonding occurs.

**Option 2: CH3-Nitrogen**
- Nitrogen has a lone pair of electrons.
- Carbon has the electronic configuration: 1s² 2s² 2p².
- Carbon does not have vacant d orbitals.
- **Conclusion**: p-pi d-pi bonding does not occur.

**Option 3: CCl3-**
- Carbon has a lone pair of electrons.
- Chlorine has the electronic configuration: 1s² 2s² 2p⁶ 3s² 3p⁵ 3d⁰.
- Chlorine has vacant d orbitals, so it can accept the lone pair from carbon.
- **Conclusion**: p-pi d-pi bonding occurs.

**Option 4: CF3-**
- Carbon has a lone pair of electrons.
- Fluorine has the electronic configuration: 1s² 2s² 2p⁵.
- Fluorine does not have vacant d orbitals.
- **Conclusion**: p-pi d-pi bonding does not occur.

### Final Answer
The compounds that involve p-pi d-pi bonding are:
- **Option 1: SiH3-Nitrogen**
- **Option 3: CCl3-**