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DMg


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
SymbolMeaning
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 24MgD
StateTeomegaeomegaexeomegaeyeBealphaegammaeDebetaereTrans.nu00
G 2Sigma+     [3.26] 1   [0.8E-4]  [1.668] G rarrow X V 46071.4 Z
Khan, 1962
D 2Sigma- (42080) (1180) 2   [3.273]   [1.0E-4]  [1.665] D rarrow A V 22860.0 Z
missing citation
C 2Pi(r) (41180) [1140.1] Z   3.256 3 4 0.073  0.92E-4  1.669 C rarrow A V 21940 5
missing citation
           C lrarrow X V 41214.2 6 Z
Guntsch, 1935; Turner and Harris, 1937; missing citation; Balfour, 1970
StateTeomegaeomegaexeomegaeyeBealphaegammaeDebetaereTrans.nu00
E 2Sigma+  7   [3.20] 7    [1.684] E larrow X VR 35549.0 Z
missing citation
B' 2Sigma+ 22410.3 597.5 Z 6.05 8  [1.350] 9  0.25E-4 0.043E-4 2.596 B' rarrow X 10 R 22172.7 Z
Guntsch, 1939
A 2Pir 19235.5 11 1154.75 Z 16.675 12 -0.1833 3.2190 0.06795 13 -0.001225 0.964E-4 0.0089E-4 1.6788 A lrarrow X V 19273.71 6 Z
missing citation; Balfour, 1970; Balfour and Cartwright, 1975
X 2Sigma+ 0 1077.89 Z 16.12 14 0.085 3.0306 0.06289 -0.00144 0.921E-4 15  1.7302  

Notes

1R branch breaks off at N'=12.
2Estimated from w2 = 4B3/D and from the observed isotope shift of the 0-0 band.
3B(R,P) - B(Q) ~ +0.008.
4 missing citation reports breaking-off of P and R branches in the CrarrowX, 0-0 band above N'=14. No line broadening is observed in the absorption spectrum Balfour, 1970.
5Average of the two subband origins Guntsch, 1939.
6Refers in the upper state to the zero point of the Hill-Van Vleck equation.
7Fragments of what is probably the ElarrowX, 1-0 band have been found Khan, 1963 between 36690 and 36930 cm-1. Two additional levels, formerly attributed to a separate 2Sigma+ state (B 2Sigma), have been identified at 39593.8 cm-1 [in emission missing citation and absorption Khan, 1963, Bv = 2.862] and at 38330.3 cm-1 [in absorption Khan, 1963, Bv-1= 2.915].
8De ~ 11200 cm-1 Guntsch, 1939.
9Bv(v=1)= 1.355, Bv(v=2)= 1.359, Bv(v=4)= 1.358, Bv(v=5)= 1.354, Bv(v=6)= 1.346; Be= 1.346. No emission from v'=3 has been found. Small perturbations by A 2Pi.
10RKR Franck-Condon factors Guntsch, 1939.
11A0= +35.04, A1= 36.1, A2= 36.7.
12De ~ 15500 cm-1 Balfour and Cartwright, 1975.
13Small perturbations by B' 2Sigma.
14weze= -0.0293; fourth order fit to the DeltaG values of Balfour and Cartwright, 1975 whose equilibrium constants do not satisfactorily reproduce their data. De0 ~ 11500 cm-1 Balfour and Cartwright, 1975.
15+0.012E-4 (v+1/2) +...
16From the value for MgH, in good agreement with an extrapolation of the ground state vibration levels.

References

Go To: Top, Constants of diatomic molecules, Notes

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

Khan, 1962
Khan, M.A., MgH bands at 2172, 2100 and 2088 Å and MgD bands at 2172, 2358 and 2364 A, Proc. Phys. Soc. London, 1962, 80, 209. [all data]

Guntsch, 1935
Guntsch, A., Uber das ultraviolette bandenspektrum des magnesiumhydrids und magnesiumdeutrids, Z. Phys., 1935, 93, 534. [all data]

Turner and Harris, 1937
Turner, L.A.; Harris, W.T., The ultraviolet bands of magnesium hydride, Phys. Rev., 1937, 52, 626. [all data]

Balfour, 1970
Balfour, W.J., The electronic spectrum of magnesium hydride and magnesium deuteride, J. Phys. B:, 1970, 3, 1749. [all data]

Guntsch, 1939
Guntsch, Dissertation, Stockholm, 1939, 1. [all data]

Balfour and Cartwright, 1975
Balfour, W.J.; Cartwright, H.M., The ground state and A2«PI» excited state of magnesium deuteride, Can. J. Phys., 1975, 53, 1477. [all data]

Khan, 1963
Khan, M.A., Ultra-violet spectrum of MgH and MgD, Proc. Phys. Soc. London, 1963, 82, 572. [all data]


Notes

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