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Magnesium chloride

Constants of diatomic molecules

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Klaus P. Huber and Gerhard H. Herzberg

Data collected through March, 1977

Symbols used in the table of constants
State electronic state and / or symmetry symbol
Te minimum electronic energy (cm-1)
ωe vibrational constant – first term (cm-1)
ωexe vibrational constant – second term (cm-1)
ωeye vibrational constant – third term (cm-1)
Be rotational constant in equilibrium position (cm-1)
αe rotational constant – first term (cm-1)
γe rotation-vibration interaction constant (cm-1)
De centrifugal distortion constant (cm-1)
βe rotational constant – first term, centrifugal force (cm-1)
re internuclear distance (Å)
Trans. observed transition(s) corresponding to electronic state
ν00 position of 0-0 band (units noted in table)
Diatomic constants for 24Mg35Cl
Fragments of four band systems at 12700 Querbach, 1930, 25900 Parker, 1935, 37060 and 40850 cm-1 [ Harrington, 1942, abs.].
B 2Sigma 47630 [552.0] H         B rarrow A V 21136.8 H
Rao and Rao, 1963
            21191.9 1 H
Rao and Rao, 1963
A 2Pi (1/2) 26523.4 491.6 H 2.54 -0.025 [0.25116] (0.0018)  0.225E-6  [2.1720] A lrarrow X 2 V 26535.89 Z
Morgan, 1936; Morgan and Barrow, 1961
A 2Pi (3/2) 26469.4    [0.24914] 3 (0.0018)  0.225E-6  [2.1808] A lrarrow X 2 V 26481.95 Z
Morgan, 1936; Morgan and Barrow, 1961
X 2Sigma+ 0 [462.12] Z 2.10  0.24502 0.00158  0.252E-6  2.1991  


1No clear identification of the various isotopic band heads was possible.
2The assignment of the emission band heads by Parker, 1935, is not correct.
3From Morgan and Barrow, 1961. Somewhat different results in Patel and Patel, 1968.
4Thermochemical value (mass-spectrometry); average of three reactions Hildenbrand, 1970, Farber and Srivastava, 1976.


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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Querbach, 1930
Querbach, J., Uber die spektra von Fe, La, Ca, Ba, Sr, Mg und ihrer verbindungen im nahen ultrarot, Z. Phys., 1930, 60, 109. [all data]

Parker, 1935
Parker, A.E., Band systems of MgCl, CaCl, and SrCl, Phys. Rev., 1935, 47, 349. [all data]

Harrington, 1942
Harrington, Dissertation, University of California, California, 1942, 0. [all data]

Rao and Rao, 1963
Rao, V.S.; Rao, P.T., Emission spectrum of MgCl: a new doublet system, Indian J. Phys., 1963, 37, 640. [all data]

Morgan, 1936
Morgan, F., Band spectra of MgCl, MgBr and MgI in absorption, Phys. Rev., 1936, 50, 603. [all data]

Morgan and Barrow, 1961
Morgan, E.; Barrow, R.F., Rotational analysis of the A2«PI»-X2«SIGMA»+ system of MgCl, Nature (London), 1961, 192, 1182. [all data]

Patel and Patel, 1968
Patel, M.M.; Patel, P.D., 2«PI»1/2 rotational analysis of the A2«PI»1/2 --> X2«SIGMA»+ system of the MgCl molecule, Indian J. Phys., 1968, 42, 254. [all data]

Hildenbrand, 1970
Hildenbrand, D.L., Dissociation energies and chemical bonding in the alkaline-earth chlorides from mass spectrometric studies, J. Chem. Phys., 1970, 52, 5751. [all data]

Farber and Srivastava, 1976
Farber, M.; Srivastava, R.D., The dissociation energy of magnesium chloride, Chem. Phys. Lett., 1976, 42, 567. [all data]


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