Home Symbol which looks like a small house Up Solid circle with an upward pointer in it

Iodine monochloride

Data at NIST subscription sites:

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.

Constants of diatomic molecules

Go To: Top, References, Notes

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 January, 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 127I35Cl
Fragments of many Rydberg series in the absorption spectrum above 60000 cm-1 have been observed and tabulated by Venkateswarlu, 1975; see also Donovan and Robertson, 1972. The intensities in these series are most irregular, possibly because of perturbations by valence states in this region. The Rydberg series are believed to converge to two limits at 81362 and 85996 cm-1 corresponding to the 2Pi3/2 and 2Pi1/2, v=0 components of the ground state of ICl+.
missing citation
L 71006 [420] H 1         L larrow X V 71024
missing citation; missing citation
G 66484 [421] H 2         G larrow X V 66503 H
missing citation; missing citation
Extensive system of absorption bands in the region 60250 - 63300 cm-1, not yet analyzed.
Venkateswarlu, 1975
F 58167 [445] H 3         F lrarrow X V 58198 H
Cordes and Sponer, 1932; Haranath and Rao, 1957; missing citation; missing citation
E 53477 [434] H 4         E lrarrow X V 53502 H
Cordes and Sponer, 1932; Haranath and Rao, 1957; missing citation; missing citation
Continuous absorption with maximum at 41600 cm-1.
Seery and Britton, 1964
D 37585 173.2 H 1.1 5        D rarrow A 6 R 23824 H
missing citation
Asundi and Venkateswarlu, 1947
Seery and Britton, 1964
B' 0+ (18157) [32] 9         B' larrow X R 17981 H
Brown and Gibson, 1932
B 3Pi0+ 17363.1 221.1 10 Z 9.62  0.0872 10 11 0.0017  (10E-8)  2.66 B larrow X 12 R 17279.5 10 Z
Brown and Gibson, 1932; Hulthen, Jarlsater, et al., 1961
A 3Pi1 13742 212.3 13 H 2.39 14 -0.012 0.084832 15   (5.4E-8)  2.6923 A lrarrow X 16 17 R 13656 13 H
missing citation; Hulthen, Johansson, et al., 1958; Hulthen, Jarlsater, et al., 1961; missing citation
X 1Sigma+ 0 384.293 Z 1.501  0.1141587 18 0.0005354  (4.03E-8)  2.320878 19  
Brooks and Crawford, 1955
Raman sp. 20
Holzer, Murphy, et al., 1970
Microwave sp. 21
Townes, Merritt, et al., 1948; Herbst and Steinmetz, 1972


1Strong progression, F larrow X of Donovan and Husain, 1968, n5 of Venkateswarlu, 1975.
2Strong progression, E larrow X of Donovan and Husain, 1968, g5 of Venkateswarlu, 1975.
3Extensive band system, formerly D - X, b6 of Venkateswarlu, 1975.
4Extensive band system, formerly C - X, a6 of Venkateswarlu, 1975.
5Extensive band system.
6Constants of Haranath and Rao, 1957, for the lower state (omega"e= 209.7, omega"ex"e = 1.9), are not in agreement with the work of Clyne and Coxon, 1967 and Cummings and Klemperer, 1974 concerning the A 3Pi1 state; see Clyne and Coxon, 1967. This system was also observed in fluorescence following two-step laser excitation DlarrowAlarrowX Barnes, Moeller, et al., 1974. (Note that nue given by Haranath and Rao, 1957 does not match their observed nu00.)
7Diffuse emission bands between 18700 and 21700 cm-1.
8Continuous absorption with maximum at 21000 cm-1. 24
9Potential well arising from the avoided crossing of the "original" B 3Pi0+ curve going to I (2P3/2) + Cl (2P1/2) and the repulsive 0+ curve coming from unexcited atoms; see also Child and Bernstein, 1973. 25
10Extrapolated from data with v'= 1,2,3.
11v'=4 is strongly predissociated and gives rise to broad, diffuse absorption bands; no higher levels are observed. At high resolution Olson and Innes, 1976 even v'=3 shows appreciable broadening of the individual lines which rapidly increases above J'=37 and is presumably caused by predissociation into the 0+ state arising from 2P3/2 + 2P3/2; see B' 0+. The non-radiative lifetime varies from ~0.2 ns at low J to 0.02 ns at J=42 Olson and Innes, 1976.
12The f value is estimated to be (f= 0.0026) Olson and Innes, 1976 corresponding to a radiative lifetime of tau= 1 mus Olson and Innes, 1976.
13Vibrational constants from Clyne and Coxon, 1967, whose measurements of the I + Cl chemiluminescence spectrum include bands with v'= 1...18. Cummings and Klemperer, 1974, extrapolating from the data (zero lines) of Hulthen, Jarlsater, et al., 1961 for 3 leq v' leq 19, nu00 = 13655.23 Cummings and Klemperer, 1974. Earlier, from band origins with 7leqv'leq19, Hulthen, Jarlsater, et al., 1961, derived omegae = 209.111 Hulthen, Jarlsater, et al., 1961, omegaexe = 1.886 Hulthen, Jarlsater, et al., 1961, omegaeye = -0.03558 Hulthen, Jarlsater, et al., 1961, nu00 = 13660.29 Hulthen, Jarlsater, et al., 1961. See 14.
14 Clyne and Coxon, 1967. Tv values for 38 levels (vgeq3) are listed in Hulthen, Jarlsater, et al., 1961. There is a strong vibrational perturbation above v=34, but the last few levels are again regular and converge to 17366.0 cm-1.
15Be = B0 = 0.084583, 3leqvleq19 Cummings and Klemperer, 1974, B1 = 0.083995, 3leqvleq19 Cummings and Klemperer, 1974, B2 = 0.083308, 3leqvleq19 Cummings and Klemperer, 1974, have been extrapo1ated by Cummings and Klemperer, 1974, from the Bv values of Hulthen, Jarlsater, et al., 1961 for 3leqvleq19. Bv values up to v=40 are tabulated in Hulthen, Jarlsater, et al., 1961. The Lambda-type doubling constant q [~B(R,P)-B(Q)] increases from +1.32E-5 for v=10 to +11.0E-5 for v=27, but the doubling becomes irregular at higher v values Hulthen, Jarlsater, et al., 1961. The dipole moment in A 3Pi1 varies from 2.00 D at v=7 to 0.6 D at v=27 Cummings and Klemperer, 1974; sign opposite to that in X 1Sigma+. RKR potential curve Coxon, 1973.
16Fluorescence lifetimes of 110 and 76 mus have been measured. Holleman and Steinfeld, 1971 following laser excitation at 6068 and 5922 Å, respectively.
17Magnetic rotation spectrum Eberhardt, Cheng, et al., 1959; its intensity drops sharply above v'=28. See also Stalder and Eberhardt, 1967. Laser induced fluorescence series in argon matrix Wight, Ault, et al., 1975.
18From the microwave spectrum Herbst and Steinmetz, 1972; in excellent agreement with the much earlier values from the electronic spectrum Curtis and Patkowski, 1934.
19Infrared sp. 21
20Resonance Raman spectrum in argon matrix Wight, Ault, et al., 1975.
21muel(v=0) 1.24 D Herbst and Steinmetz, 1972; dipole derivative 2.1 D/Å Brooks and Crawford, 1955. Electric quadrupole coupling constants for I and Cl in Herbst and Steinmetz, 1972, also iodine spin-rotation constant.
22From the convergence limit of A 3Pi1, see 14.
23Average value obtained by photoelectron spectroscopy Potts and Price, 1971, Cornford, 1971 and photoion mass- spectrometry Dibeler, Walker, et al., 1971.
24At least partly due to BlarrowX; see the discussion in Coxon, 1973.
25There are fragments of fairly sharp branches at places corresponding to extrapolated levels of B 3Pi0+.


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.

Venkateswarlu, 1975
Venkateswarlu, P., The vacuum ultraviolet spectrum of ICl, Can. J. Phys., 1975, 53, 812. [all data]

Donovan and Robertson, 1972
Donovan, R.J.; Robertson, P.J., Vacuum ultraviolet spectrum of ICl, Spectrosc. Lett., 1972, 5, 281. [all data]

Cordes and Sponer, 1932
Cordes, H.; Sponer, H., Die molekulabsorption der gemischten halogenmolekule im vakuumultraviolett. II. Mitteilung, Z. Phys., 1932, 79, 170. [all data]

Haranath and Rao, 1957
Haranath, P.B.V.; Rao, P.T., Emission spectra of mixed halogens. Part I: ICl, Indian J. Phys., 1957, 31, 156. [all data]

Seery and Britton, 1964
Seery, D.J.; Britton, D., The continuous absorption spectra of chlorine, bromine, bromine chloride, iodine chloride, and iodine bromide, J. Phys. Chem., 1964, 68, 2263. [all data]

Asundi and Venkateswarlu, 1947
Asundi, R.K.; Venkateswarlu, P., On continous emission bands of ICl and IBr, Indian J. Phys., 1947, 21, 76-82. [all data]

Brown and Gibson, 1932
Brown, W.G.; Gibson, G.E., Predissociation in the spectrum of iodine chloride, Phys. Rev., 1932, 40, 529. [all data]

Hulthen, Jarlsater, et al., 1961
Hulthen, E.; Jarlsater, N.; Koffman, L., On the absorption spectrum of ICl. Part II. Chlorine isotopes in iodine chloride, Ark. Fys., 1961, 18, 479. [all data]

Hulthen, Johansson, et al., 1958
Hulthen, E.; Johansson, N.; Pilsater, U., On the absorption spectrum of ICl. Part I, Ark. Fys., 1958, 14, 31. [all data]

Brooks and Crawford, 1955
Brooks, W.V.F.; Crawford, B., Jr., Vibrational intensities. V. BrCl and ICl, J. Chem. Phys., 1955, 23, 363. [all data]

Holzer, Murphy, et al., 1970
Holzer, W.; Murphy, W.F.; Bernstein, H.J., Resonance Raman effect and resonance fluoroscence in halogen gases, J. Chem. Phys., 1970, 52, 399. [all data]

Townes, Merritt, et al., 1948
Townes, C.H.; Merritt, F.R.; Wright, B.D., The pure rotational spectrum of ICl, Phys. Rev., 1948, 73, 1334. [all data]

Herbst and Steinmetz, 1972
Herbst, E.; Steinmetz, W., Dipole moment of ICl, J. Chem. Phys., 1972, 56, 5342. [all data]

Donovan and Husain, 1968
Donovan, R.J.; Husain, D., Photochemical studies of IBr, ICl and BrCl by kinetic spectroscopy in the vacuum ultra-violet, Trans. Faraday Soc., 1968, 64, 2325. [all data]

Clyne and Coxon, 1967
Clyne, M.A.A.; Coxon, J.A., The formation and detection of some low-lying excited electronic states of BrCl and other halogens, Proc. R. Soc. London A, 1967, 298, 424. [all data]

Cummings and Klemperer, 1974
Cummings, F.E.; Klemperer, W., Vibrational dependence of the dipole moment in the A3«PI»1 state of ICl, J. Chem. Phys., 1974, 60, 2035. [all data]

Barnes, Moeller, et al., 1974
Barnes, R.H.; Moeller, C.E.; Kircher, J.F.; Verber, C.M., Two-step excitation of fluorescence in iodine monochloride vapor, Appl. Phys. Lett., 1974, 24, 610. [all data]

Child and Bernstein, 1973
Child, M.S.; Bernstein, R.B., Diatomic interhalogens: systematics and implications of spectroscopic interatomic potentials and curve crossings, J. Chem. Phys., 1973, 59, 5916. [all data]

Olson and Innes, 1976
Olson, C.D.; Innes, K.K., Single-rotational-level lifetimes from measurements of linewidths in the B3«PI»o+ <-- X1«SIGMA»+ system of ICl, J. Chem. Phys., 1976, 64, 2405. [all data]

Coxon, 1973
Coxon, J.A., Chapt. 4. Low-lying electronic states of diatomic halogen molecules in Molecular Spectroscopy. Volume 1, Barrow,R.F.; Long,D.A.; Millen,D.J., ed(s)., The Chemical Society, Burlington House, London, W1V 0BN, 1973, 177-228. [all data]

Holleman and Steinfeld, 1971
Holleman, G.W.; Steinfeld, J.I., Time-resolved fluorescence of iodine monochloride, Chem. Phys. Lett., 1971, 12, 431. [all data]

Eberhardt, Cheng, et al., 1959
Eberhardt, W.H.; Cheng, W.-C.; Renner, H., The magnetic rotation spectrum of ICl and IBr, J. Mol. Spectrosc., 1959, 3, 664. [all data]

Stalder and Eberhardt, 1967
Stalder, A.F.; Eberhardt, W.H., Magnetically induced circular dichroism and birefringence in single lines of the electronic spectrum of ICl, J. Chem. Phys., 1967, 47, 1445. [all data]

Wight, Ault, et al., 1975
Wight, C.A.; Ault, B.S.; Andrews, L., Laser-induced fluorescence and resonance Raman spectra of interhalogen diatomics isolated in inert matrices at 12 K, J. Mol. Spectrosc., 1975, 56, 239. [all data]

Curtis and Patkowski, 1934
Curtis, W.E.; Patkowski, J., XI. Rotational analysis of the absorption bands of ICl, Philos. Trans. R. Soc. London A, 1934, 232, 395. [all data]

Potts and Price, 1971
Potts, A.W.; Price, W.C., Photoelectron spectra of the halogens and mixed halides ICI and lBr, J. Chem. Soc. Faraday Trans., 1971, 67, 1242. [all data]

Cornford, 1971
Cornford, Thesis, University of British Columbia, 1971, 0. [all data]

Dibeler, Walker, et al., 1971
Dibeler, V.H.; Walker, J.A.; McCulloh, K.E.; Rosenstock, H.M., Effect of hot bands on the ionization threshold of some diatomic halogen molecules, Intern. J. Mass Spectrom. Ion Phys., 1971, 7, 209. [all data]


Go To: Top, Constants of diatomic molecules, References