Cesium dimer
- Formula: Cs2
- Molecular weight: 265.8109038
- IUPAC Standard InChI: InChI=1S/2Cs
- IUPAC Standard InChIKey: KNJJHXOVFHKJEY-UHFFFAOYSA-N
- CAS Registry Number: 12184-83-7
- Chemical structure:
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Gas phase thermochemistry data
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.
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔfH°gas | 25.662 | kcal/mol | Review | Chase, 1998 | Data last reviewed in December, 1983 |
| Quantity | Value | Units | Method | Reference | Comment |
| S°gas,1 bar | 68.033 | cal/mol*K | Review | Chase, 1998 | Data last reviewed in December, 1983 |
Gas Phase Heat Capacity (Shomate Equation)
Cp° = A + B*t + C*t2 + D*t3 +
E/t2
H° − H°298.15= A*t + B*t2/2 +
C*t3/3 + D*t4/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t2/2 + D*t3/3 −
E/(2*t2) + G
Cp = heat capacity (cal/mol*K)
H° = standard enthalpy (kcal/mol)
S° = standard entropy (cal/mol*K)
t = temperature (K) / 1000.
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| Temperature (K) | 298. to 1500. | 1500. to 6000. |
|---|---|---|
| A | 6.978710 | 10.09570 |
| B | 10.14290 | -4.443339 |
| C | -13.38790 | 1.294240 |
| D | 4.311860 | -0.102151 |
| E | 0.018461 | 1.373810 |
| F | 23.29970 | 25.00939 |
| G | 74.11561 | 83.48229 |
| H | 25.66109 | 25.66109 |
| Reference | Chase, 1998 | Chase, 1998 |
| Comment | Data last reviewed in December, 1983 | Data last reviewed in December, 1983 |
Gas phase ion energetics data
Go To: Top, Gas phase thermochemistry 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 as indicated in comments:
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
B - John E. Bartmess
View reactions leading to Cs2+ (ion structure unspecified)
Electron affinity determinations
| EA (eV) | Method | Reference | Comment |
|---|---|---|---|
| 0.469 ± 0.015 | LPES | McHugh, Eaton, et al., 1989 | Vertical Detachment Energy: 0.511±0.010 eV; B |
Ionization energy determinations
| IE (eV) | Method | Reference | Comment |
|---|---|---|---|
| 3.7 ± 0.1 | PI | Kappes, Radi, et al., 1985 | LBLHLM |
| ≤3.76 ± 0.06 | S | Helm and Moller, 1983 | LBLHLM |
| 3.68 | EVAL | Marr and Wherrett, 1972 | LLK |
| 3.60 | PI | Marr and Wherrett, 1972 | LLK |
| 3.8 ± 0.1 | PI | Foster, Leckenby, et al., 1969 | RDSH |
References
Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Chase, 1998
Chase, M.W., Jr.,
NIST-JANAF Themochemical Tables, Fourth Edition,
J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]
McHugh, Eaton, et al., 1989
McHugh, K.M.; Eaton, J.G.; Lee, G.H.; Sarkas, H.W.; Kidder, L.H.; Snodgrass, J.T.; Manaa, M.R.; Bowen, K.H.,
Photoelectron Spectra of the alkali metal cluster Anions: Na-,n=2-5, K-,n=2-7, Rb-,n=2-3, and Cs-,n=2-3,
J. Chem. Phys., 1989, 91, 6, 3792, https://doi.org/10.1063/1.456861
. [all data]
Kappes, Radi, et al., 1985
Kappes, M.M.; Radi, P.; Schar, M.; Schumacher, E.,
Photoionization measurements on dialkali monohalides generated in supersonic nozzle beams,
Chem. Phys. Lett., 1985, 113, 243. [all data]
Helm and Moller, 1983
Helm, H.; Moller, R.,
Bound-free spectroscopy of Cs2+,
Phys. Rev. A:, 1983, 27, 2493. [all data]
Marr and Wherrett, 1972
Marr, G.V.; Wherrett, S.R.,
The ionization of caesium vapour by the method of space charge amplification,
J. Phys. B:, 1972, 5, 1735. [all data]
Foster, Leckenby, et al., 1969
Foster, P.J.; Leckenby, R.E.; Robbins, E.J.,
The ionization potentials of clustered alkali metal atoms,
J. Phys. B:, 1969, 2, 478. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, References
- Symbols used in this document:
EA Electron affinity S°gas,1 bar Entropy of gas at standard conditions (1 bar) ΔfH°gas Enthalpy of formation of gas at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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