A molecule absorbs light at ‘X’ nm wavelength and emits light as fluorescence at ‘Y’ nm wavelength. Typically, there is a shift in the wavelength (Y>X). E is the energy transferred to the solvent during reorganization of the excited state, ‘h’ is the Planck’s constant, and ‘c’ is the speed of light.

E is equal to:

Correct option is B

EXPLANATION-

To solve this, let's start by recalling the relationship between energy and wavelength in light:

$$E = \frac{hc}{\lambda}$$

Where:
 is the energy,
ℎ  is Planck’s constant,
  is the speed of light,
 is the wavelength of light.

The energy difference between absorbed and emitted light (i.e., energy lost to the environment during relaxation) is:

                                                                                                $$E = \frac{hc}{X} - \frac{hc}{Y}$$

Taking common factor $$hc\text{:}$$

                                                              $$E = hc\left( \frac{1}{X} - \frac{1}{Y} \right) = hc \frac{Y - X}{XY}$$

So, the correct option is (b) hc(Y-X) / XY