Triclinic crystal has the following the cell parameters:

Options

A. `a=b=c, alpha=beta=gamma=90^(@)`
B. `a=bnec, alpha=beta=gamma=90^(@)`
C. `ane bne c, alpha ne beta ne gamma ne 90^(@)`
D. `ane bne c, alpha =beta=90^(@)gamma ne120^(@)`

Answer

To determine the cell parameters of a triclinic crystal system, we need to analyze the characteristics of this system based on its edge lengths and angles.

### Step-by-Step Solution:

1. **Understanding Cell Parameters**:
- In a crystal system, the cell parameters consist of three edge lengths (a, b, c) and three angles (α, β, γ) that define the geometry of the unit cell.

2. **Characteristics of Triclinic System**:
- The triclinic crystal system is defined by the following properties:
- All three edge lengths are unequal: \( a \neq b \neq c \).
- All three angles are also unequal: \( \alpha \neq \beta \neq \gamma \).
- None of the angles are equal to 90 degrees: \( \alpha \neq 90^\circ \), \( \beta \neq 90^\circ \), \( \gamma \neq 90^\circ \).

3. **Evaluating the Options**:
- **Option A**: States that all edge lengths are equal and all angles are equal to 90 degrees. This describes a cubic system, not triclinic. **(Incorrect)**
- **Option B**: States that \( a = b \) but \( a \neq c \) and all angles are equal to 90 degrees. This describes a tetragonal system, not triclinic. **(Incorrect)**
- **Option C**: States that \( a \neq b \neq c \) and \( \alpha \neq \beta \neq \gamma \), with none equal to 90 degrees. This correctly describes the triclinic system. **(Correct)**

4. **Conclusion**:
- The correct option that describes the cell parameters of a triclinic crystal system is Option C: \( a \neq b \neq c \) and \( \alpha \neq \beta \neq \gamma \), with all angles not equal to 90 degrees.