# Is it possible to calculate the refractive index of a gas mixture given the pressure, temperature and wavelength?

I am searching for a formula to calculate the refractive index at a specific point in a planetary atmosphere.

Given are pressure, temperature, wavelength and the molecular composition of the atmosphere. Is there a general formula to calculate the refractive index with these parameters? All formulas I found use a lot of magic numbers, but since my problem is so general I cannot trust any magic numbers.

If I remember corrrectly, there are general formulas and theory on the refractive index of gasses in Roger G Newton's book Scattering Theory of Waves and Particles. ISBN 978-3-642-88128-2. You do need to know something of the scattering cross sections of the individual components of the gasses.

• Thanks, I try to get my hands on this book. I accept your comment once I have it and it had the answers. – Jhonny007 May 10 at 8:34