Whether molecular ion `HeH^(Θ)` exist or not? Explain.

Explanation

To determine whether the molecular ion \( \text{HeH}^- \) exists or not, we can use Molecular Orbital Theory (MOT). Here’s a step-by-step solution:

### Step 1: Understand the Molecular Ion
The molecular ion in question is \( \text{HeH}^- \). This ion consists of one helium atom (He) and one hydrogen atom (H) with an additional electron due to the negative charge.

### Step 2: Determine the Total Number of Electrons
- Helium (He) has 2 electrons.
- Hydrogen (H) has 1 electron, but since it has a negative charge, we add an extra electron, making it a total of 2 electrons from hydrogen.
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