One side of an equilateral prism is painted by a transparent material of refractive index $$n_2$$. The refractive index of prism is 1.6. The minimum value of $$n_2$$ required for total internal reflection from painted face is ________ .

A

$$\frac{3\sqrt{3}}{1.6}$$

B

$$\sqrt{3}$$

C

$$\frac{3.2}{\sqrt{3}}$$

D

$$\frac{4\sqrt{3}}{5}$$