# mercury monoxide

**Formula:**HgO**Molecular weight:**216.59**IUPAC Standard InChI:**- InChI=1S/Hg.O
- Download the identifier in a file.

**IUPAC Standard InChIKey:**UKWHYYKOEPRTIC-UHFFFAOYSA-N**CAS Registry Number:**21908-53-2**Chemical structure:**

This structure is also available as a 2d Mol file or as a computed 3d SD file

The 3d structure may be viewed using Java or Javascript.**Other names:**Mercury(ii) oxide-
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## Gas phase thermochemistry data

**Go To:** Top, Condensed phase thermochemistry data, 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} | 41.84 | kJ/mol | Review | Chase, 1998 | Data last reviewed in June, 1962 |

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

S°_{gas,1 bar} | 239.13 | J/mol*K | Review | Chase, 1998 | Data last reviewed in June, 1962 |

### 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.

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

A | 36.41988 |

B | 1.285167 |

C | -0.226380 |

D | 0.019250 |

E | -0.360147 |

F | 29.71904 |

G | 280.8029 |

H | 41.84000 |

Reference | Chase, 1998 |

Comment | Data last reviewed in June, 1962 |

## Condensed phase thermochemistry data

**Go To:** Top, Gas phase thermochemistry data, 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°_{solid} | -90.79 ± 0.12 | kJ/mol | Review | Cox, Wagman, et al., 1984 | red phase; CODATA Review value |

_{f}H°_{solid} | -90.79 | kJ/mol | Review | Chase, 1998 | Data last reviewed in June, 1962 |

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

S°_{solid,1 bar} | 70.25 ± 0.30 | J/mol*K | Review | Cox, Wagman, et al., 1984 | red phase; CODATA Review value |

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

S°_{solid} | 70.26 | J/mol*K | Review | Chase, 1998 | Data last reviewed in June, 1962 |

### Solid 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.

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Temperature (K) | 298. - 1000. |
---|---|

A | 27.60273 |

B | 73.55556 |

C | -58.49650 |

D | 16.82299 |

E | -0.064122 |

F | -102.0222 |

G | 83.82811 |

H | -90.78903 |

Reference | Chase, 1998 |

Comment | Data last reviewed in June, 1962 |

## Constants of diatomic molecules

**Go To:** Top, Gas phase thermochemistry data, Condensed 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 February, 1975

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} |
---|---|---|---|---|---|---|---|---|---|---|---|---|

Absorption bands in the region 33900 - 36500 cm^{-1}, usually ascribed to Hg_{2}
("wing" bands), were tentatively assigned to HgO by Walter and Barratt, 1929. |

## References

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

**Chase, 1998**

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

**Cox, Wagman, et al., 1984**

Cox, J.D.; Wagman, D.D.; Medvedev, V.A.,
**CODATA Key Values for Thermodynamics**, Hemisphere Publishing Corp., New York, 1984, 1. [all data]

**Walter and Barratt, 1929**

Walter, J.M.; Barratt, S.,
*The band spectra associated with zinc, cadmium, and mercury*,
**Proc. R. Soc. London A**, 1929, 122, 201. [all data]

## Notes

**Go To:** Top, Gas phase thermochemistry data, Condensed 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) S° _{solid}Entropy of solid at standard conditions S° _{solid,1 bar}Entropy of solid at standard conditions (1 bar) _{f}H°_{gas}Enthalpy of formation of gas at standard conditions _{f}H°_{solid}Enthalpy of formation of solid at standard conditions - Data from NIST Standard Reference Database 69:
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