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# Mercury hydride

**Formula:**HHg**Molecular weight:**201.60**CAS Registry Number:**13966-62-6**Information on this page:****Data at other public NIST sites:****Options:**

## Gas phase thermochemistry 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.
**

Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|

_{f}H°_{gas} | 238.49 | kJ/mol | Review | Chase, 1998 | Data last reviewed in June, 1963 |

Quantity | Value | Units | Method | Reference | Comment |

S°_{gas,1 bar} | 219.71 | J/mol*K | Review | Chase, 1998 | Data last reviewed in June, 1963 |

### Gas Phase Heat Capacity (Shomate Equation)

C_{p}° = A + B*t + C*t^{2} + D*t^{3} +
E/t^{2}

H° − H°_{298.15}= A*t + B*t^{2}/2 +
C*t^{3}/3 + D*t^{4}/4 − E/t + F − H

S° = A*ln(t) + B*t + C*t^{2}/2 + D*t^{3}/3 −
E/(2*t^{2}) + G

C_{p} = heat capacity (J/mol*K)

H° = standard enthalpy (kJ/mol)

S° = standard entropy (J/mol*K)

t = temperature (K) / 1000.

View plot Requires a JavaScript / HTML 5 canvas capable browser.

Temperature (K) | 298. - 1200. | 1200. - 6000. |
---|---|---|

A | 19.60543 | 36.96539 |

B | 36.73569 | 2.207609 |

C | -26.73107 | -0.046724 |

D | 7.470114 | 0.003146 |

E | 0.147617 | -1.958155 |

F | 231.7267 | 222.5014 |

G | 234.4304 | 257.0566 |

H | 238.4884 | 238.4884 |

Reference | Chase, 1998 | Chase, 1998 |

Comment | Data last reviewed in June, 1963 | Data last reviewed in June, 1963 |

## Constants of diatomic molecules

**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 by:** Klaus P. Huber and Gerhard H. Herzberg

Data collected through January, 1976

Symbol | Meaning |
---|---|

State | electronic state and / or symmetry symbol |

T_{e} | minimum electronic energy (cm^{-1}) |

ω_{e} | vibrational constant – first term (cm^{-1}) |

ω_{e}x_{e} | vibrational constant – second term (cm^{-1}) |

ω_{e}y_{e} | vibrational constant – third term (cm^{-1}) |

B_{e} | rotational constant in equilibrium position (cm^{-1}) |

α_{e} | rotational constant – first term (cm^{-1}) |

γ_{e} | rotation-vibration interaction constant (cm^{-1}) |

D_{e} | centrifugal distortion constant (cm^{-1}) |

β_{e} | rotational constant – first term, centrifugal force (cm^{-1}) |

r_{e} | internuclear distance (Å) |

Trans. | observed transition(s) corresponding to electronic state |

ν_{00} | position of 0-0 band (units noted in table) |

State | T_{e} | _{e} | _{e}x_{e} | _{e}y_{e} | B_{e} | _{e} | _{e} | D_{e} | _{e} | r_{e} | Trans. | _{00} |
---|---|---|---|---|---|---|---|---|---|---|---|---|

D ^{2}^{+} 1 | [(4.7)] | [(1.8_{9})] | D X R | (37040) | ||||||||

↳Rydberg, 1932; Phillips and Davis, 1968 | ||||||||||||

C ^{2}^{+} | [4.519] 2 | [34.8E-4] 3 | [1.928_{7}] | C X R | 35587.4 Z | |||||||

↳Rydberg, 1932; Phillips and Davis, 1968; Veseth, 1972 | ||||||||||||

B ^{2}^{+} | [4,028] 4 | [16.27E-4] 5 | [2.042_{9}] | B X 6 R | 33876.47 Z | |||||||

↳Hulthen, 1928; Rydberg, 1932; Phillips and Davis, 1968; Veseth, 1972 | ||||||||||||

A_{2} ^{2}_{3/2} | 28274 | 2068.24 7 Z | 43.04 8 | 6.741_{1} 7 9 | 0.2295 10 | [2.818E-4] 7 11 | 1.5791 | A_{2} X 12 V | 28616.23 13 Z | |||

↳Rydberg, 1932; Fujioka and Tanaka, 1938; Porter, 1962; Porter and Davis, 1962; Phillips and Davis, 1968 | ||||||||||||

State | T_{e} | _{e} | _{e}x_{e} | _{e}y_{e} | B_{e} | _{e} | _{e} | D_{e} | _{e} | r_{e} | Trans. | _{00} |

A_{1} ^{2}_{1/2} | [1939.18] 7 Z | 14 | [6.5609] 7 15 16 | 17 | [2.850E-4] 7 18 | [1.6007] | A_{1} X 12 V_{R} | 24933.10 13 Z | ||||

↳Rydberg, 1932; Fujioka and Tanaka, 1938; missing citation; Porter and Davis, 1962; Porter and Davis, 1963; Phillips and Davis, 1968; missing citation; Stwalley, 1975 | ||||||||||||

X ^{2}^{+} | 0 | [1203.24] 7 Z | 19 | [5.3888] 7 16 20 21 | 22 | [3.953E-4] 7 23 | [1.7662_{0}] 24 | |||||

↳Kosman and Hinze, 1975; Stwalley, 1975 |

### Notes

1 | Fragments only. |

2 | Spin doubling _{12}= [2.71 - 0.0093N(N+1)](N+1/2), increasing rapidly
above N=17. See also Veseth, 1973. |

3 | H_{0} = +3.42E-6. |

4 | Spin doubling _{12} = [1.11 - 0.00374N(N+1)](N+1/2), increasing very
rapidly above N = 19. See also Veseth, 1973. |

5 | H_{0} = +2.04E-6. |

6 | Q branches weak in 0-0, strong in 0-1 and 0-2, not observed in 0-3. |

7 | These are effective constants; "true" vibronic energies and rotational constants calculated by Veseth, 1972. |

8 | _{e}x_{e}= -0.052_{0}(v+1/2)^{4} [v=0,..., 6]. |

9 | Perturbations. |

10 | _{v}= +0.0083_{9}(v+1/2)^{2} - 0.0013_{0}(v+1/2)^{3} [v=0,..., 6]. |

11 | D_{1}(E-4 cm^{-1})= 2.880,
D_{2}(E-4 cm^{-1})= 2.867,
D_{3}(E-4 cm^{-1})= 3.182;
H_{0}(E-8 cm^{-1}) = +0.09,
H_{1}(E-8 cm^{-1})= +0.07,
H_{2}(E-8 cm^{-1})= -5.4,
H_{3}(E-8 cm^{-1})= +2.46. |

12 | Hg "nuclear" isotope shifts; see Porter and Davis, 1962. |

13 | Constants in Phillips and Davis, 1968 are slightly different since they refer to J' = 1/2 or 3/2 instead of {J'= 0} relative to N"= 0. |

14 | G(3/2) = 1809.66,G(5/2)= 1509.13. |

15 | -type doubling _{fe}(v=0) = +3.360(J+1/2)- ... Phillips and Davis, 1968; decreasing with
increasing v, but very anomalous in v=3. See also Veseth, 1973. |

16 | Magnetic hyperfine structure in X ^{2}^{+} and A_{1} ^{2}_{1/2} of
^{199}HgH and ^{201}HgH, see Porter and Davis, 1963, Eakin and Davis, 1970. |

17 | B_{1} = 6.3239, B_{2} = 6.0271(perturbation by v=0 of A_{2}), B_{3} = 5.104 (very
anomalous, see 18). |

18 | D_{1}(E-4 cm^{-1}) = 2.952, D_{2}(E-4 cm^{-1})= 3.462, D_{3}(E-4 cm^{-1})= -18.42;
H_{0}(E-8 cm^{-1}) = +0.082,
H_{1}(E-8 cm^{-1})= -1.21,
H_{2}(E-8 cm^{-1})= -18.4,
H_{3}(E-8 cm^{-1})= -31. |

19 | G(3/2) = 965.34 Stwalley, 1975,G(5/2)= 632.53 Stwalley, 1975,G(7/2)= 167.82 Stwalley, 1975. G(0) = 681.2 Stwalley, 1975 |

20 | Spin doubling _{12}(v=0) = +2.14_{4}(N+1/2) - ... Fujioka and Tanaka, 1938, Eakin and Davis, 1970; decreasing rapidly
with increasing v Fujioka and Tanaka, 1938, Eakin and Davis, 1970. |

21 | Predissociation by rotation. Lines with N" > 29, 22, 15 in v" = 0,1,2, respectively, are broad. Lines with N" > 30, 24, 18, 8, 6 in v"=0, ..., 4, respectively, are absent Rydberg, 1933, Porter, 1962*, Eakin and Davis, 1970. |

22 | B_{1}= 4.9512, B_{2}= 4.3473, B_{3}= 3.2510, B_{4}= 1.451. |

23 | D_{1}(E-4 cm^{-1}) = 5.016,
D_{2}(E-4 cm^{-1})= 8.08,
D_{3}(E-4 cm^{-1})= 33.87,
D_{4}(E-4 cm^{-1})= 40.7;
H_{0}(E-8 cm^{-1}) = -0.06,
H_{1}(E-8 cm^{-1})= -4.99,
H_{2}(E-8 cm^{-1})= -21.4,
H_{3}(E-8 cm^{-1})= -1490; higher order constants in Phillips and Davis, 1968. |

24 | ESR sp. 26 Potential curve |

25 | From the predissociation in X ^{2}^{+} of the hydride and deuteride Stwalley, 1975. See also Fig.
189 of MOLSPEC, Vol. 1. |

26 | In solid Ar matrix at 4 K Knight and Weltner, 1971. |

## References

**Go To:** Top, Gas phase thermochemistry 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.
**

**Chase, 1998**

Chase, M.W., Jr.,
*NIST-JANAF Themochemical Tables, Fourth Edition*,
**J. Phys. Chem. Ref. Data, Monograph 9**, 1998, 1-1951. [all data]

**Rydberg, 1932**

Rydberg, R.,
*Uber das bandenspektrum des quecksilberhydrids*,
**Z. Phys.**, 1932, 73, 74. [all data]

**Phillips and Davis, 1968**

Phillips, J.G.; Davis, S.P.,
**Berkely analyses of molecular spectra**, Pub. University of California Press, Berkeley and Los Angeles, 1968, 0. [all data]

**Veseth, 1972**

Veseth, L.,
*Fine structure and perturbations in the electronic spectra of HgH and HgD*,
**J. Mol. Spectrosc.**, 1972, 44, 251. [all data]

**Hulthen, 1928**

Hulthen, E.,
*Neuere unterschungen uber das bandenspektrum des quecksilberhydrids*,
**Z. Phys.**, 1928, 50, 319. [all data]

**Fujioka and Tanaka, 1938**

Fujioka, Y.; Tanaka, Y.,
*On the molecular spectra ^{2}«PI»-->^{2}«SIGMA» of mercury hydride and deuteride. I. ^{2}«SIGMA» state*,

**Sci. Pap. Inst. Phys. Chem. Res. Jpn.**, 1938, 34, 713. [all data]

**Porter, 1962**

Porter, T.L.,
*Band-spectrum analysis of mercury hydride*,
**J. Opt. Soc. Am.**, 1962, 52, 11, 1201-1205. [all data]

**Porter and Davis, 1962**

Porter, T.L.; Davis, S.P.,
*Isotope shift in the spectrum of mercury hydride*,
**J. Opt. Soc. Am.**, 1962, 52, 1206. [all data]

**Porter and Davis, 1963**

Porter, T.L.; Davis, S.P.,
*Hyperfine structure in the spectrum of mercury hydride*,
**J. Opt. Soc. Am.**, 1963, 53, 338. [all data]

**Stwalley, 1975**

Stwalley, W.C.,
*Mass-reduced quantum numbers: application to the isotopic mercury hydrides*,
**J. Chem. Phys.**, 1975, 63, 3062. [all data]

**Kosman and Hinze, 1975**

Kosman, W.M.; Hinze, J.,
*Inverse perturbation analysis: improving the accuracy of potential energy curves*,
**J. Mol. Spectrosc.**, 1975, 56, 93. [all data]

**Veseth, 1973**

Veseth, L.,
*Hund's coupling case (c) in diatomic molecules. II. Examples*,
**J. Phys. B:**, 1973, 6, 1484. [all data]

**Eakin and Davis, 1970**

Eakin, D.M.; Davis, S.P.,
*Band spectra and hyperfine structure of HgH, HgD, and HgT*,
**J. Mol. Spectrosc.**, 1970, 35, 27. [all data]

**Rydberg, 1933**

Rydberg, R.,
*Uber einige potentialkurven des quecksilberhydrids*,
**Z. Phys.**, 1933, 80, 514. [all data]

**Knight and Weltner, 1971**

Knight, L.B., Jr.; Weltner, W., Jr.,
*Hyperfine interaction, chemical bonding, and isotope effect in ZnH, CdH, and HgH molecules*,
**J. Chem. Phys.**, 1971, 55, 2061. [all data]

## Notes

**Go To:** Top, Gas phase thermochemistry data, Constants of diatomic molecules, References

- Symbols used in this document:

S° _{gas,1 bar}Entropy of gas at standard conditions (1 bar) _{f}H°_{gas}Enthalpy of formation of gas at standard conditions - Data from NIST Standard Reference Database 69:
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