H-ZF10 by CDGM

$$n(\lambda) = \sqrt{1 + \frac{1.5006\,\lambda^2}{\lambda^2 - 145.496} + \frac{1.57641\,\lambda^2}{\lambda^2 - 0.0121805} + \frac{0.183076\,\lambda^2}{\lambda^2 - 0.060514}}$$

$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[-5.43 \times 10^{-6} + 2(1.06 \times 10^{-8})\,\Delta T + 3(-9.67 \times 10^{-11})\,\Delta T^2 + \frac{9.25 \times 10^{-7} + 2(1.66 \times 10^{-9})\,\Delta T}{\lambda - 0.269}\right] \Delta T = T - T_0, \quad T_0 = 20\,°\text{C}$$