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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 July, 1976

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 40CaD
F 2Sigma+ (36698) [1036.1] Z 14 1  2.434 0.051  [0.000049] 2  1.901 F larrow X V 36771.4 Z
Edvinsson, Kopp, et al., 1963; Khan, 1966; Khan and Afridi, 1968
M 2Delta (4d)     3       
J 2Pi (4d)     3      J larrow X 35034.16 4
Kaving and Lindgren, 1976
G 2Sigma+ (4d)     3      G larrow X (34750)
Kaving and Lindgren, 1976; Khan, 1966
L 2Pi (5p) (32647) 5 [1020.57] 6 (15.9)  [2.3830] 6 0.0412  [0.00005018] 6 7  1.9125 L larrow X 32713.61 6
Kaving and Lindgren, 1976
K 2Sigma+ (5p) (32615) [(1012)] 6   [2.3751] 6 8 (0.019)  [0.0000503] 6  1.920 K larrow X 32665.5 6
Kaving and Lindgren, 1976
C 2Sigma+     [(2.35)] 6   [0.000044]  [(1.93)] C rarrow X V 28322 Z
missing citation; missing citation
B 2Sigma+     2.282 9 0.045  [0.000054] 10  1.963 B rarrow X V 15748.8 Z
Watson, 1935
X 2Sigma+ 0 [910.4] Z   [2.1769] 11 0.035  [0.0000479] 12  2.0016  


1From isotope relations.
2D1= 0.30E-4.
3Term values, but no constants, determined Kaving and Lindgren, 1976 for v=0 of J 2Pi and G 2Sigma. M 2Delta not observed with certainty. G 2Sigma(v=0) is perturbed by L 2Pi(v=2). Smaller local perturbations in J 2Pi.
4Q11(1/2) line.
5A0= +19.48, A1= +19.3.
6Deperturbed constants for the two interacting states which form the p complex. Small local perturbations.
7D1= 0.495E-4; H1= -1.25E-9.
8F1 levels not observed, presumably on account of predissociation. In v=1 both spin components seem to be predissociated.
9Effective value. Spin-splitting constant gamma ~ -0.364, but see Veseth, 1971.
10D1= 0.65E-4.
11Spin-splitting constant gamma0= +0.0216.
12D1= 0.61E-4
13From the predissociation in C 2Sigma+, assuming dissociation into Ca(3P) + H(2S).
14Strong perturbations. Breaking off above v'=0, N'=18.


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

Edvinsson, Kopp, et al., 1963
Edvinsson, G.; Kopp, I.; Lindgren, B.; Aslund, N., Rotational analysis of an ultraviolet system of the hydrides and deuterides of Ca, Sr and Ba, Ark. Fys., 1963, 25, 95. [all data]

Khan, 1966
Khan, M.A., CaH band at 2883 Å and CaD bands at 2720 Å, 2789 Å and 2877 Å, Proc. Phys. Soc. London, 1966, 87, 569. [all data]

Khan and Afridi, 1968
Khan, M.A.; Afridi, M.K., A high dispersion study of some new absorption bands of CaH and CaD in the ultra-violet region, J. Phys. B:, 1968, 1, 260. [all data]

Kaving and Lindgren, 1976
Kaving, B.; Lindgren, B., Ultraviolet absorption spectrum of the CaH molecule. III. A comparison between CaH and CaD spectra in the region 2800-3200 Å, Phys. Scr., 1976, 13, 39-46. [all data]

Watson, 1935
Watson, W.W., Comparison of the spectra of CaH and CaD, Phys. Rev., 1935, 47, 27. [all data]

Veseth, 1971
Veseth, L., An investigation of the interaction between close-lying 2«SIGMA» and 2«PI» states of diatomic molecules. I. Spin-splitting of the 2«SIGMA» levels, Mol. Phys., 1971, 20, 1057. [all data]


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