Which of the following has zero electron density in xy plane ?

Options

A. `d_(z^(2))`
B. `d_(x^(2)- y^(2))`
C. `p_(z)`
D. `d_(xy)`

Explanation

To determine which of the given orbitals has zero electron density in the XY plane, we can analyze the characteristics of each orbital.

### Step-by-Step Solution:

1. **Understanding the XY Plane**:
The XY plane is defined by the x and y coordinates, meaning we are looking for an orbital that does not have any electron density in this plane.

**Hint**: Remember that the Z-axis is perpendicular to the XY plane.

2. **Analyzing the Orbitals**:
- **Option 1: dz² Orbital**:
The dz² orbital can be represented as \(d_{z^2} = d_{x^2 - y^2} + d_{z^2}\). This orbital has components in both the x and y directions, meaning there will be electron density in the XY plane.

**Hint**: Check if the orbital involves x or y coordinates.

- **Option 2: x² - y² Orbital**:
This orbital is purely dependent on the x and y coordinates. Therefore, it also has electron density in the XY plane.

**Hint**: If the orbital is a function of x and y, it will have electron density in the XY plane.

- **Option 3: pz Orbital**:
The pz orbital is defined by its dependence on the z coordinate, meaning it has no dependence on x or y. Thus, there is no electron density in the XY plane.

**Hint**: Identify if the orbital is dependent solely on the z-coordinate.

3. **Conclusion**:
Based on the analysis, the only orbital that has zero electron density in the XY plane is the pz orbital.

### Final Answer:
The correct answer is **Option 3: pz Orbital**.