Calcium monohydride
- Formula: CaH
- Molecular weight: 41.086
- IUPAC Standard InChI: InChI=1S/Ca.H
- IUPAC Standard InChIKey: PKHCKQOIOXDRJH-UHFFFAOYSA-N
- CAS Registry Number: 14452-75-6
- Chemical structure:
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Gas phase ion energetics data
Go To: Top, Constants of diatomic molecules, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled as indicated in comments:
B - John E. Bartmess
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
Electron affinity determinations
| EA (eV) | Method | Reference | Comment |
|---|---|---|---|
| 0.930 ± 0.050 | PD | Rackwitz, Feldman, et al., 1977 | B |
Ionization energy determinations
| IE (eV) | Method | Reference | Comment |
|---|---|---|---|
| 5.86 ± 0.09 | S | Kaving and Lindgren, 1974 | LLK |
De-protonation reactions
Ca- + =
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 352.80 ± 0.93 | kcal/mol | D-EA | Petrunin, Andersen, et al., 1996 | gas phase; B |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 347.0 ± 1.0 | kcal/mol | H-TS | Petrunin, Andersen, et al., 1996 | gas phase; B |
Constants of diatomic molecules
Go To: Top, Gas phase ion energetics data, 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 July, 1976
| Symbol | Meaning |
|---|---|
| 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) |
| State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| I (2Σ) | [(4.60)] | [(1.93)] | I ← X | (39477) | ||||||||
| ↳Khan and Afridi, 1968 | ||||||||||||
| H (2Σ) | [(4.41)] | [(1.97)] | H ← X | (38798) | ||||||||
| ↳Khan and Afridi, 1968 | ||||||||||||
| F 2Σ+ | 36705 | 1487 1 | 28 | [4.6867] | [0.0002017] | [1.9128] | F ← X V | 36979.05 Z | ||||
| ↳Khan, 1962; missing citation; Khan and Afridi, 1968 | ||||||||||||
| M 2Δ (4d) | 2 | [4.89] 3 | [1.87] | M ← X | 35481.8 3 | |||||||
| ↳missing citation | ||||||||||||
| State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
| J 2Π (4d) | 2 | [4.898] 3 | [2.8] 3 | [1.871] | J ← X | 35068.53 3 | ||||||
| ↳missing citation | ||||||||||||
| G 2Σ+ (4d) | (34735) 2 | [1458] 4 | [4.765] 3 | [1.17] 3 | [1.897] | G ← X | 34819.5 3 | |||||
| ↳missing citation | ||||||||||||
| L 2Π (5p) | (32680) 5 | [1407.6] 6 | [4.6204] 6 | 0.1139 | [1.920] 6 7 | 1.9148 | L ← X | 32739.37 6 | ||||
| ↳missing citation | ||||||||||||
| K 2Σ+ (5p) | (32640) | [(1391)] 6 | [4.601] 6 8 | (0.085) | [1.93] 6 9 | 1.922 | K ← X | 32691.1 6 | ||||
| ↳missing citation | ||||||||||||
| State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
| C 2Σ+ | 28276 | 1445 H | 25 | [4.58] 10 11 | [1.7] 10 | [1.94] | C ↔ X V | 28348 10 | ||||
| ↳missing citation; missing citation; Grundstrom, 1935 | ||||||||||||
| D 2Σ+ | 22602 | 1150 Z | 33.0 | 2.50 12 | 0.01 | 2.62 | D → X R | 22524 Z | ||||
| ↳Grundstrom, 1931; Grundstrom, 1932 | ||||||||||||
| E 2Π | 20418 13 | 1248.6 HQ | 21.8 | [4.284] | [2.2] | [2.001] | E → X 14 V | 20392 Z | ||||
| ↳Watson and Weber, 1935 | ||||||||||||
| B 2Σ+ (4p) | 15762 | 1285 | 20 | [4.3410] 15 | 0.116 | [2.020] 15 16 | 1.9744 | B ↔ X V | 15754.96 15 | |||
| ↳Hulthen, 1927; Watson and Bender, 1930; missing citation; Liberale and Weniger, 1969; Berg and Klynning, 1974; Berg and Klynning, 1974, 2 | ||||||||||||
| State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
| A 2Πr (4p) | 14413 17 | 1333 | 20 | [4.34769] 15 | 0.106 | [1.883] 15 18 | 1.9740 | A ↔ X V | 14430.39 15 | |||
| ↳Hulthen, 1927; Watson and Bender, 1930; Mulliken and Christy, 1931; Liberale and Weniger, 1969; Berg and Klynning, 1974; Berg and Klynning, 1974, 2 | ||||||||||||
| X 2Σ+ | 0 | 1298.34 Z | 19.10 | 4.2766 19 | 0.0970 | 1.837 20 | 2.0025 21 | |||||
Notes
| 1 | From isotope relations Edvinsson, Kopp, et al., 1963. |
| 2 | A0 = +5.0. |
| 3 | Deperturbed constants for the three interacting states which form the d complex. The 2Δ5/2 component was not observed. Most of the lines are somewhat diffuse. The 2Π-2Σ band whose low J lines are sharp had been misinterpreted by Khan and Hasnain, 1973 in terms of two overlapping 2Σ-2Σ transitions. Small local perturbations. |
| 4 | From the proposed assignment of the 1-0 band by Khan and Afridi, 1968. Kaving and Lindgren, 1974 observe a diffuse single branch only. |
| 5 | A0= +18.8, A1= +19.3. |
| 6 | Deperturbed constants for the two interacting states which form the p complex. Small local perturbations. |
| 7 | D1 = 2.064E-4; H0 = +4.7E-9. |
| 8 | F1 levels not observed, presumably on account of predissociation. In v=1 both spin components seem to be predissociated. |
| 9 | H0= +2.5E-9. |
| 10 | Constants derived from high N values. At low N, v=0 is perturbed by a state of smaller B value. The observed origin of the 0-0 band is at 28352.5 cm-1. |
| 11 | At low pressure predissociation above v=0, N=10. |
| 12 | Strong perturbations for higher N values. |
| 13 | A ~ 9.3. |
| 14 | Two Q heads. |
| 15 | Deperturbed constants for the strongly interacting states A 2Π and B 2Σ+: see Berg and Klynning, 1974. For an extensive discussion of the rotational structure of the two states (including spin and Λ-type doubling) see also Veseth, 1971, Veseth, 1971, 2, Veseth, 1971, 3. |
| 16 | H0= +4.31E-9. |
| 17 | A0= +79.01; slight J dependence Berg and Klynning, 1974. See also Veseth, 1971. |
| 18 | H0= +5.08E-9. |
| 19 | Spin-splitting constant γv= +0.0429 - 0.0010(v+1/2). |
| 20 | He= +5.51E-9. |
| 21 | ESR sp. 24 |
| 22 | From the predissociation in C 2Σ+, assuming dissociation into Ca(3P) + H(2S). |
| 23 | From the observation of Rydberg states in the absorption spectrum Kaving and Lindgren, 1974. |
| 24 | In Ar matrix at 4 K Knight and Weltner, 1971. |
References
Go To: Top, Gas phase ion energetics data, 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.
Rackwitz, Feldman, et al., 1977
Rackwitz, R.; Feldman, D.; Kaiser, H.J.; Heincke, E.,
Photodetachment bei einigen zweiatomigen negativen hydridionen: BeH-, MgH-, CaH-, ZnH-, PH-, AsH-,
Z. Naturforsch. A:, 1977, 32, 594. [all data]
Kaving and Lindgren, 1974
Kaving, B.; Lindgren, B.,
Ultraviolet absorption spectrum of the CaH molecule. II. The structure of the d-complex around 2850 A,
Phys. Scr., 1974, 10, 81. [all data]
Petrunin, Andersen, et al., 1996
Petrunin, V.V.; Andersen, H.H.; Balling, P.; Andersen, T.,
Structural Properties of the Negative Calcium Ion: Binding Energies and Fine-structure Splitting,
Phys. Rev. Lett., 1996, 76, 5, 744, https://doi.org/10.1103/PhysRevLett.76.744
. [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]
Khan, 1962
Khan, M.A.,
A new band in CaH at 2720 Å and discussion of the hydrides of metals of group II,
Proc. Phys. Soc. London, 1962, 80, 593. [all data]
Grundstrom, 1935
Grundstrom, B.,
Die bandenspektra des calciumhydrids. III,
Z. Phys., 1935, 95, 574. [all data]
Grundstrom, 1931
Grundstrom, B.,
Die bandenspektra des calciumhydrids. I.,
Z. Phys., 1931, 69, 235. [all data]
Grundstrom, 1932
Grundstrom, B.,
Die bandenspektra des calciumhydrids. II,
Z. Phys., 1932, 75, 302. [all data]
Watson and Weber, 1935
Watson, W.W.; Weber, R.L.,
The E band system of calcium hydride,
Phys. Rev., 1935, 48, 732. [all data]
Hulthen, 1927
Hulthen, E.,
On the band spectrum of calcium hydride,
Phys. Rev., 1927, 29, 97. [all data]
Watson and Bender, 1930
Watson, W.W.; Bender, W.,
The Zeeman effect in the red CaH bands,
Phys. Rev., 1930, 35, 1513. [all data]
Liberale and Weniger, 1969
Liberale, G.; Weniger, S.,
Etude du spectre d'absorption des systemes A2Π-X2Σ et B2Σ-X2Σ de l'hydrure de calcium,
Physica (Amsterdam), 1969, 41, 47. [all data]
Berg and Klynning, 1974
Berg, L.-E.; Klynning, L.,
Rotational analysis of the A-X and B-X band systems of CaH,
Phys. Scr., 1974, 10, 331. [all data]
Berg and Klynning, 1974, 2
Berg, L.-E.; Klynning, L.,
New laboratory measurments of the A2Π-X2Σ and B2Σ-X2Σ transitions of CaH,
Astron. Astrophys. Suppl. Ser., 1974, 13, 325. [all data]
Mulliken and Christy, 1931
Mulliken, R.S.; Christy, A.,
Λ-type doubling and electron configurations in diatomic molecules,
Phys. Rev., 1931, 38, 87. [all data]
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 and Hasnain, 1973
Khan, M.A.; Hasnain, S.S.,
Two overlapping systems of CaH and CaD in the UV region,
Nuovo Cimento B, 1973, 18, 384. [all data]
Veseth, 1971
Veseth, L.,
Corrections to the spin-orbit splitting in 2Π states of diatomic molecules,
J. Mol. Spectrosc., 1971, 38, 228. [all data]
Veseth, 1971, 2
Veseth, L.,
An investigation of the interaction between close-lying 2Σ and 2Π states of diatomic molecules. I. Spin-splitting of the 2Σ levels,
Mol. Phys., 1971, 20, 1057. [all data]
Veseth, 1971, 3
Veseth, L.,
An investigation of the interaction between close-lying 2Σ and 2Π states of diatomic molecules. II. Λ-doubling of the 2Π levels,
Mol. Phys., 1971, 21, 287. [all data]
Knight and Weltner, 1971
Knight, L.B., Jr.; Weltner, W., Jr.,
Hyperfine interaction and chemical bonding in MgH, CaH, SrH, and BaH molecules,
J. Chem. Phys., 1971, 54, 3875. [all data]
Notes
Go To: Top, Gas phase ion energetics data, Constants of diatomic molecules, References
- Symbols used in this document:
EA Electron affinity ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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