The stark splitting of millimeter wave transitions of water

Abstract

Thi s pa pe r fir st di sc usses th e tec hniqu e of mak ing S ta rk meas u re me nt s a t millim ete r wave' le ng th s. Th e de tail s of correcting for res idu a l ove rl a p betwee n th e lin es, th e effec ts of modu la ti on , a nd of th e fi e ld inh o moge ne it y a re di sc usse d. Finall y th e meas ure d fre qu e nc ies a nd th e e mpiri ca l S ta rk coe ffi cie nt s for one H,O, a nd one D,O, an d fiv e HDO lin es be tw ee n 85 and 250 GHz a re give n .Th e fi na l a nalys is of the data to giv e values of th e dipole mome nt wi ll be give n in a noth e r pap er.Key word s: Millimeter wav es; S ta rk e ffec t; wat e r.

Zero-frequency refractivity of water vapor, comparison of Debye and van-Vleck Weisskopf theory

“…An alternative to the early measurements of refractivity [1][2][3][4][5][6] to determine the dipole moment of water µ is to measure the Stark splitting of the water vapor rotational lines [20][21][22], which is independent of the number density of water vapor molecules. The more recent Stark measurements at the frequencies of 22.235 GHz and 183.310 GHz [21,22], have obtained µ = 1.848 Debye. In addition, molecular beam electric resonance spectroscopy measurements [23,24], of the Stark splitting of the hyperfine lines in rotational states of H 2 O have obtained µ = 1.855 Debye, which is considered to be the most accurate value.…”