Grischkowsky D, Yang Yihong, Mandehgar Mahboubeh
School of Electrical and Computer Engineering, Oklahoma State University, Stillwater, Oklahoma 74078, USA.
Opt Express. 2013 Aug 12;21(16):18899-908. doi: 10.1364/OE.21.018899.
We show that the zero-frequency, refractivity of water vapor calculated by the van-Vleck Weisskopf theory via a summation over all the water lines from 22.2 GHz to 30 THz can explain all of the previous measurements from 0.5 MHz to microwave, mm-waves and THz frequencies. This result removes a long standing discrepancy in comparisons of measurements and theory, and is in excellent agreement with experiments.
