Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review

Absorption of Resonance Radiation in Mercury Vapor

A. Ll. Hughes, A. R. Thomas

Published Oct 1, 1927• 14 citations
Publisher

Abstract

The absorption of the resonance radiation (2536A) of mercury was studied by dividing the radiation from a resonance lamp into two parts, each part going into a separate photo-electric cell. An absorption cell containing mercury vapor whose pressure could be controlled by cooling a side tube was placed in the path of one beam. The ratio of the amount of light passing into each beam could be varied by a mechanical device. From the setting of the mechanical device, giving a balance between the two photo-electric currents, the absorption of the mercury vapor could be inferred. The absorption per atom was calculated and found to decrease rapidly as the total amount of absorbing vapor was increased, thus showing that the resonance radiation is not homogeneous. The maximum atomic absorption coefficient was 11\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}14}$, which indicates that an atom can stop the radiation which falls upon an area one hundred times larger than its cross sectional area.

DOI
10.1103/physrev.30.466

Related papers

Hyperfine Structure Absorption in Optically Excited Mercury Vapor

M. L. Pool, S. J. Simmons

The radiation 4047, 2967 and 2752, all terminating on the $2^{3}P_{0}$ state of mercury, was passed through optically excited mercury vapor and the absorption of each wavelength for various lengths of excited vapor and for various pressures of admixed nitrogen was measured photometrically. With low dispersion the intensity of 2752 decreased nearly exponentially with increase in length of excited vapor giving a constant linear absorption coefficient. But the lines 4047 and 2967 were found not to obey the exponential law, the fractional decrease in intensity per unit length of path decreased rapidly as the total length of the absorbing vapor increased. With high dispersion the absorption of the five components of 4047 was strong and increased with increase of admixed nitrogen. The strongest component showed the strongest absorption and the amount of absorption decreased with decrease in intensity of components. The intensity of each component decreased nearly exponentially with increase in length of excited mercury vapor. Both components of 2967 showed strong absorption. None of the components of 4358 or 5461 showed measurable absorption.

Physical Review•Dec 15, 1933•1 citation

Absorption of Resonance Radiation in Mercury Vapor

Ancil R. Thomas

The theories of absorption in mercury vapor of mercury resonance light of wave-length 2536.7A as formulated by Malinowski and H. A. Wilson are briefly reviewed. It is well established that the absorption coefficient for resonance radiation increases as the number of absorbing atoms decreases. This is probably due to a Doppler effect in the radiating vapor. To diminish the influence of the Doppler effect a jet of mercury vapor was used, and the resonance radiation coming from it was investigated. A series of measurements of the absorption coefficient of this light is given. The maximum atomic absorption coefficient observed is 10.22\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}13}$, nine times as large as any previously observed. It is shown that Malinowski's assumptions are not in accord with the observed effects.

Physical Review•May 15, 1930•4 citations

Controlled orbital transfers of electrons in optically excited mercury atoms

Robert Williams Wood

Abstract As I have shown in numerous publications, the vapour of mercury in vacuo, even at temperatures below the solidifying point of the metal, when illuminated by the light of a water-cooled quartz mercury lamp, emits the monochromatic radiation of wave-length 2536. According to Bohr’s theory, this resonance radiation results from the fall of an electron from the 2p2 orbit, to which it has been raised from the IS orbit by the absorption of one quantum of 2536 radiation, back to the IS orbit, the orbit occupied by the electron when the atom is in its normal state. An atom in which the electron has been brought to the 2p2 orbit is in a condition to absorb the radiation of any other line produced by the fall of electrons from outer orbits to orbit 2p2, and Fuchtbauer has shown, in an extremely interesting and important paper (‘Physik. Zeit.,’ 1920), that a large number of the arc lines of mercury are radiated by cold mercury vapour illuminated by the mercury arc. He showed that, if the 2536 radiation was screened off by glass, none of the other lines appeared, and explained their presence as the result of the absorption by excited atoms with electrons at the 2p2 level, of the radiations terminating at this level, by which the electrons are carried out to other-orbits, from which they can fall back in various ways, giving rise to emission lines in the process. Though Fuchtbauer‘s experiment did not prove that this process actually took place, his explanation was the only one possible on modern theory, and the experiments which are to be considered in the present paper show that it was correct. Twenty years ago the most that could have been said would have been that the absorption of the 2536 radiation “shook” the atom in some way, causing it to emit its other frequencies as a sort of fluorescence, since Fuchtbauer’s experiment did not show that excitation by lines other than the 2536 line was necessary for the emission of the arc spectrum. To demonstrate experimentally that the step-by-step transfer of electrons from orbit to orbit actually takes place, it is necessary to illuminate the mercury vapour with various combinations of monochromatic light, and study the resultant emission spectrum.

Proceedings of the Royal Society of London Series A Containing Papers of a Mathematical and Physical Character•Dec 1, 1924•28 citations

The Sensitized Fluorescence of Potassium

Ernst H. Krause

A mixture of potassium vapor and mercury vapor contained in a tube fashioned after the Cario-Lochte-Holtgreven sodium vapor lamp was radiated by light from a water-cooled mercury arc. The resulting fluorescence radiation contained potassium lines as well as two of the three known ${\mathrm{K}}_{2}$ absorption bands and a new band with maximum at 5721A. On exposure of the mixture to light from a hot mercury arc or to light having all wave-lengths shorter than 2800A filtered out, the fluorescence was eliminated. This indicated that the excitation was caused by absorption of 2536A by the mercury. Absorption of the 2536A mercury line raises the mercury atom to the $6^{3}P_{1}$ state, having an energy of 4.86 volts. The ionization potential of potassium is 4.32 volts; thus in a collision of the second kind, the excited mercury atom has enough energy to ionize the potassium atom. There was no evidence of a potassium emission from an energy state in the continuum equal in energy to the Hg $6^{3}P_{1}$ or $6^{3}P_{0}$ states. There were, however, two strong lines in fluorescence which could not be ascribed to the usual K energy levels nor to any probable impurity. To test whether or not ionization of potassium actually takes place, a filament was introduced into the tube to supply electrons. A large increase in intensity of the fluorescence of potassium lines was obtained with the hot filament. It was furthermore found that the intensity increased with filament temperature.

Physical Review•Jan 15, 1939•1 citation

LIFETIME OF THE 6$sup 3$P$sub 1$ EXCITED STATE OF MERCURY VAPOR FOR THE ISOTOPES WITH EVEN AND ODD MASSES

J.-L. Cojan, M. Thibeau

The measurement of the absorption of a parallel light beam from a resonance lamp by an absorption tube filled with mercury vapor leads to the determination ot the lifetime of the 6/sup 3/P/sub 1/ excited state of mercury. The same value ( lambda = 1.16 x 10/sup -7/ sec) was found for all the isoiopes of mercury. (tr-auth)

Compt. rend.•Oct 15, 1959•0 citations

Measurement of the Life of the Metastable Mercury Atom

M. L. Pool

Half value time for the ${2}^{3}$${\mathrm{P}}_{0}$ state of Hg for various pressures of admixed ${\mathrm{N}}_{2}$--- A high speed rotating disk has been used to interrupt the total radiation from a water-cooled and magnetically controlled quartz mercury arc before optically exciting mercury vapor in a quartz resonance tube at room temperature. In the neighborhood of ${10}^{\ensuremath{-}4}$ sec. after the optical excitation a flash of visible radiation from another water-cooled and magnetically controlled mercury arc was passed through the resonance tube and the absorption spectrum photographed. The line 4047 ($2^{3}P_{0}\ensuremath{-}2^{3}S_{1}$) showed strong absorption when a few millimeters of nitrogen were introduced into the resonance tube. The lines 4077, 4358, 5461, 5770 and 5790 showed no measurable absorption under similar conditions. The rate of decay of the amount of 4047 absorbed with respect to the time-wait after excitation of the mercury vapor was taken as the rate of decay of the metastable $2^{3}P_{0}$ state. The life or half-value time of the state was found to vary markedly with the pressure of admixed nitrogen. The maximum life 4.2\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}4}$ sec. occurred for 6.8 mm of nitrogen. No absorption of 4047 was observed upon the introduction of hydrogen, argon, neon, or helium into the resonance tube.

Physical Review•Jan 1, 1929•14 citations
The absorption of the resonance radiation (2536A) of mercury was studied by dividing the radiation from a resonance lamp into two parts, each part going into a separate photo-electric cell. An absorption cell containing mercury vapor whose pressure could be controlled by cooling a side tube was placed in the path of one beam. The ratio of the amount of light passing into each beam could be varied by a mechanical device. From the setting of the mechanical device, giving a balance between the two photo-electric currents, the absorption of the mercury vapor could be inferred. The absorption per atom was calculated and found to decrease rapidly as the total amount of absorbing vapor was increased, thus showing that the resonance radiation is not homogeneous. The maximum atomic absorption coefficient was 11\ifmmode\times\else\texttimes\fi{}10\ensuremath−14{10}^{\ensuremath{-}14}10\ensuremath−14, which indicates that an atom can stop the radiation which falls upon an area one hundred times larger than its cross sectional area.
The radiation 4047, 2967 and 2752, all terminating on the 23P02^{3}P_{0}23P0​ state of mercury, was passed through optically excited mercury vapor and the absorption of each wavelength for various lengths of excited vapor and for various pressures of admixed nitrogen was measured photometrically. With low dispersion the intensity of 2752 decreased nearly exponentially with increase in length of excited vapor giving a constant linear absorption coefficient. But the lines 4047 and 2967 were found not to obey the exponential law, the fractional decrease in intensity per unit length of path decreased rapidly as the total length of the absorbing vapor increased. With high dispersion the absorption of the five components of 4047 was strong and increased with increase of admixed nitrogen. The strongest component showed the strongest absorption and the amount of absorption decreased with decrease in intensity of components. The intensity of each component decreased nearly exponentially with increase in length of excited mercury vapor. Both components of 2967 showed strong absorption. None of the components of 4358 or 5461 showed measurable absorption.
The theories of absorption in mercury vapor of mercury resonance light of wave-length 2536.7A as formulated by Malinowski and H. A. Wilson are briefly reviewed. It is well established that the absorption coefficient for resonance radiation increases as the number of absorbing atoms decreases. This is probably due to a Doppler effect in the radiating vapor. To diminish the influence of the Doppler effect a jet of mercury vapor was used, and the resonance radiation coming from it was investigated. A series of measurements of the absorption coefficient of this light is given. The maximum atomic absorption coefficient observed is 10.22\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}13}$, nine times as large as any previously observed. It is shown that Malinowski's assumptions are not in accord with the observed effects.
Abstract As I have shown in numerous publications, the vapour of mercury in vacuo, even at temperatures below the solidifying point of the metal, when illuminated by the light of a water-cooled quartz mercury lamp, emits the monochromatic radiation of wave-length 2536. According to Bohr’s theory, this resonance radiation results from the fall of an electron from the 2p2 orbit, to which it has been raised from the IS orbit by the absorption of one quantum of 2536 radiation, back to the IS orbit, the orbit occupied by the electron when the atom is in its normal state. An atom in which the electron has been brought to the 2p2 orbit is in a condition to absorb the radiation of any other line produced by the fall of electrons from outer orbits to orbit 2p2, and Fuchtbauer has shown, in an extremely interesting and important paper (‘Physik. Zeit.,’ 1920), that a large number of the arc lines of mercury are radiated by cold mercury vapour illuminated by the mercury arc. He showed that, if the 2536 radiation was screened off by glass, none of the other lines appeared, and explained their presence as the result of the absorption by excited atoms with electrons at the 2p2 level, of the radiations terminating at this level, by which the electrons are carried out to other-orbits, from which they can fall back in various ways, giving rise to emission lines in the process. Though Fuchtbauer‘s experiment did not prove that this process actually took place, his explanation was the only one possible on modern theory, and the experiments which are to be considered in the present paper show that it was correct. Twenty years ago the most that could have been said would have been that the absorption of the 2536 radiation “shook” the atom in some way, causing it to emit its other frequencies as a sort of fluorescence, since Fuchtbauer’s experiment did not show that excitation by lines other than the 2536 line was necessary for the emission of the arc spectrum. To demonstrate experimentally that the step-by-step transfer of electrons from orbit to orbit actually takes place, it is necessary to illuminate the mercury vapour with various combinations of monochromatic light, and study the resultant emission spectrum.
A mixture of potassium vapor and mercury vapor contained in a tube fashioned after the Cario-Lochte-Holtgreven sodium vapor lamp was radiated by light from a water-cooled mercury arc. The resulting fluorescence radiation contained potassium lines as well as two of the three known K2{\mathrm{K}}_{2}K2​ absorption bands and a new band with maximum at 5721A. On exposure of the mixture to light from a hot mercury arc or to light having all wave-lengths shorter than 2800A filtered out, the fluorescence was eliminated. This indicated that the excitation was caused by absorption of 2536A by the mercury. Absorption of the 2536A mercury line raises the mercury atom to the 63P16^{3}P_{1}63P1​ state, having an energy of 4.86 volts. The ionization potential of potassium is 4.32 volts; thus in a collision of the second kind, the excited mercury atom has enough energy to ionize the potassium atom. There was no evidence of a potassium emission from an energy state in the continuum equal in energy to the Hg 63P16^{3}P_{1}63P1​ or 63P06^{3}P_{0}63P0​ states. There were, however, two strong lines in fluorescence which could not be ascribed to the usual K energy levels nor to any probable impurity. To test whether or not ionization of potassium actually takes place, a filament was introduced into the tube to supply electrons. A large increase in intensity of the fluorescence of potassium lines was obtained with the hot filament. It was furthermore found that the intensity increased with filament temperature.
LIFETIME OF THE 6sup3sup 3sup3Psub1sub 1sub1 EXCITED STATE OF MERCURY VAPOR FOR THE ISOTOPES WITH EVEN AND ODD MASSES
Half value time for the 23{2}^{3}23P0{\mathrm{P}}_{0}P0​ state of Hg for various pressures of admixed N2{\mathrm{N}}_{2}N2​--- A high speed rotating disk has been used to interrupt the total radiation from a water-cooled and magnetically controlled quartz mercury arc before optically exciting mercury vapor in a quartz resonance tube at room temperature. In the neighborhood of ${10}^{\ensuremath{-}4}$ sec. after the optical excitation a flash of visible radiation from another water-cooled and magnetically controlled mercury arc was passed through the resonance tube and the absorption spectrum photographed. The line 4047 ($2^{3}P_{0}\ensuremath{-}2^{3}S_{1}$) showed strong absorption when a few millimeters of nitrogen were introduced into the resonance tube. The lines 4077, 4358, 5461, 5770 and 5790 showed no measurable absorption under similar conditions. The rate of decay of the amount of 4047 absorbed with respect to the time-wait after excitation of the mercury vapor was taken as the rate of decay of the metastable 23P02^{3}P_{0}23P0​ state. The life or half-value time of the state was found to vary markedly with the pressure of admixed nitrogen. The maximum life 4.2\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}4}$ sec. occurred for 6.8 mm of nitrogen. No absorption of 4047 was observed upon the introduction of hydrogen, argon, neon, or helium into the resonance tube.