An expression for a dimensionless quantity \( P \) is given by \( P = \frac{\alpha}{\beta} \log_e \left( \frac{k t}{\beta x} \right) \); where \( \alpha \) and \( \beta \) are constants, \( x \) is distance; \( k \) is Boltzmann constant and \( t \) is the temperature. Then the dimensions of \( \alpha \) will be: