hydrogen fluoride

Formula: FH
Molecular weight: 20.00634
IUPAC Standard InChI: InChI=1S/FH/h1H
IUPAC Standard InChIKey: KRHYYFGTRYWZRS-UHFFFAOYSA-N
CAS Registry Number: 7664-39-3
Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
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Isotopologues:
- [2H]hydrogen fluoride
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Gas phase thermochemistry data

Go To: Top, Constants of diatomic molecules, References, Notes

Quantity	Value	Units	Method	Reference	Comment
Δ_fH°_gas	-273.30 ± 0.70	kJ/mol	Review	Cox, Wagman, et al., 1984	CODATA Review value
Δ_fH°_gas	-272.55	kJ/mol	Review	Chase, 1998	Data last reviewed in June, 1977
Quantity	Value	Units	Method	Reference	Comment
S°_{gas,1 bar}	173.779 ± 0.003	J/mol*K	Review	Cox, Wagman, et al., 1984	CODATA Review value
S°_{gas,1 bar}	173.78	J/mol*K	Review	Chase, 1998	Data last reviewed in June, 1977

Gas Phase Heat Capacity (Shomate Equation)

C_p° = 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
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. to 1000.	1000. to 6000.
A	30.11693	24.57033
B	-3.246612	6.893391
C	2.868116	-1.243874
D	0.457914	0.082583
E	-0.024861	-0.234060
F	-281.4912	-279.7653
G	210.9226	202.8525
H	-272.5462	-272.5462
Reference	Chase, 1998	Chase, 1998
Comment	Data last reviewed in June, 1977	Data last reviewed in June, 1977

Constants of diatomic molecules

Go To: Top, Gas phase thermochemistry data, References, Notes

Data compiled by: Klaus P. Huber and Gerhard H. Herzberg

Data collected through January, 1977

Symbols used in the table of constants
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_ex_e	vibrational constant – second term (cm^-1)
ω_ey_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
ν₀₀	position of 0-0 band (units noted in table)

Diatomic constants for H¹⁹F
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
Rydberg 1	Rydberg levels converging to the ground state of HF⁺ have been observed in the electronic energy loss spectrum.
D ¹Σ⁺ 1											D ← X
D ¹Σ⁺ 1	↳di Londardo and Douglas, 1973
C ¹Π	(105820)	[2636]			[16.0]					[1.04₉]	C ← X R	105090.8
C ¹Π	↳di Lonardo and Douglas, 1972; di Londardo and Douglas, 1973
b ³Π 2											b ← X
b ³Π 2	↳di Lonardo and Douglas, 1972
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
B ¹Σ⁺	84776.65	1159.18 Z	18.005 3	0.184	4.0291 4	0.0177 5		1.932E-4 6		2.0908₆	B ↔ X 7 R	83304.96 Z
B ¹Σ⁺	↳Johns and Barrow, 1959; missing citation
A	Continuous absorption starting at 60600 cm^-1. 8
A	↳Safari, 1954
X ¹Σ⁺	0	4138.32 9 Z	89.88 10		20.9557 9 11 12	0.798 13		21.51E-4 14		0.91680₈ 15
	↳Mann, Thrush, et al., 1961; Herget, Deeds, et al., 1962; Fishburne and Rao, 1966; Webb and Rao, 1968
	Rotation sp. 16 17
	↳Rothschild, 1964; Revich and Stankevich, 1966; Mason and Nielsen, 1967
	Mol. Beam el. Reson. 18
	↳Weiss, 1963; Muenter and Klemperer, 1970; Muenter, 1972; de Leeuw and Dymanus, 1973
	Mol. Beam magn. Reson. 19
	↳Baker, Nelson, et al., 1961

Notes

Two strong bands between 104000 and 116000 cm^-1, not yet analysed.

Absorption bands above 100000 cm^-1, not yet analysed.

The vibrational and rotational constants, were obtained from a fit to the seven lowest vibrational levels di Londardo and Douglas, 1973. See 7.

RKR potential curves Fallon, Vanderslice, et al., 1960, di Londardo and Douglas, 1973.

-0.000950(v+1/2)² + 0.000060l(v+1/2)³; see 3.

+0.182E-4(v+1/2) + 0.00551E-4(v+1/2)²; see 3.

Very extensive band system (also called V-X) extending in absorption from 96000 to 117000, in emission from 36000 to 70000 cm^-1. Strong perturbations above v'=27, but bands have been identified to v'=73. The B (or V) state was also observed in the electron energy loss spectrum Salama and Hasted, 1976.

HF is quite transparent to 1650 Safari, 1954. Theoretical potential curves for three repulsive states (³Π, ¹Π, ³Σ⁺) arising from ground state atomic products were given by Dunning, 1976.

Introduction of the Dunham correction Webb and Rao, 1968 gives ω_e = 4138.767 Webb and Rao, 1968 and B_e = 20.9561.

+0.90(v+1/2)³ - 0.0ll0(v+1/2)⁴ - 0.00067(v+1/2)⁵, v≤9 Webb and Rao, 1968. A different formula for higher vibrational levels (v≤19) was derived by Johns and Barrow, 1959. All levels up to the last (v=19) are tabulated in di Londardo and Douglas, 1973).

For v=14,...19 the rotational levels break off at decreasing J on account of predissociation by rotation. A few broadened lines near these limits have been observed di Londardo and Douglas, 1973. From the limiting curve the dissociation energy 47333 ± 60 cm^-1 has been determined di Londardo and Douglas, 1973.

RKR potential curves Fallon, Vanderslice, et al., 1960, di Londardo and Douglas, 1973, Dunham potential coefficients Webb and Rao, 1968, Ogilvie and Koo, 1976. Ab initio calculations of molecular constants Bondybey, Pearson, et al., 1972, Krauss and Neumann, 1974, Meyer and Rosmus, 1975, Dunning, 1976.

+0.0127(v+1/2)² - 0.00044(v+1/2)³ , from Webb and Rao, 1968.

-0.68E-4(v+1/2)+0.029E-4(v+1/2)², H_e = 1.59E-7; from Webb and Rao, 1968; see also Mann, Thrush, et al., 1961.

Rot.-vibr. Sp. 22 23 17

Laser emission in the pure rotation spectrum Deutsch, 1967.

Rotation and rotation-vibration spectra in rare-gas matrices Mason, von Holle, et al., 1971.

μ_el(v=0,J=1) = 1.82618 D Muenter and Klemperer, 1970, Muenter, 1972; g_J = 0.7410, quadrupole moment Θ_m= 2.36E-26 esu cm² de Leeuw and Dymanus, 1973; also nuclear spin - rotation and other hyperfine structure constants.

Nuclear reorientation spectrum.

From the limiting curve of dissociation for the ground state di Londardo and Douglas, 1973; see 11.

From photoelectron spectra Walker, Dehmer, et al., 1973, Guyon, Spohr, et al., 1976. Earlier photoionization studies yielded 16.00₇ eV Berkowitz, Chupka, et al., 1971, a value strongly affected by the presence of autoionizing Rydberg levels in the threshold region Guyon, Spohr, et al., 1976. The second ionization potential (removal of a 3σ electron) from the photoelectron spectrum Berkowitz, 1971, Guyon, Spohr, et al., 1976 is 19.118 eV in agreement with the value derived from the spectrum of HF⁺. The third and fourth ionization potentials (removal of a 2σ and 1σ electron, respectively) are 39.61 Banna and Shirley, 1975, Shaw and Thomas, 1975 and 694.25 eV Shaw and Thomas, 1975; these are vertical potentials from X-ray photoelectron spectra.

1-0, 2-0 bands studied in absorption under high resolution by Herget, Deeds, et al., 1962, Webb and Rao, 1968, 3-0, 4-0, 5-0 in the photographic infrared by Naude and Verleger, 1950, Fishburne and Rao, 1966. In emission, rotation-vibration bands have been studied by Mann, Thrush, et al., 1961 and Sileo and Cool, 1976, the latter extending the chemical laser emission, first observed in the 2-1 band by Kompa and Pimentel, 1967, to v=9 and Δv=6. Electric discharge induced laser emission in the 3-2, 2-1, 1-0 bands, see Deutsch, 1967, 2, Coldhar, Osgood, et al., 1971.

Line strengths, collision-broadened widths, dipole moment function Meredith, 1972, Spellicy, Meredith, et al., 1972, Lie, 1974, Rimpel, 1974, Sileo and Cool, 1976, Yardley and Balint-Kurti, 1976. The radiative lifetime of v=1 [P(4) line] is 6.16 ms Hinchen, 1974. Sileo and Cool, 1976 give a vibrational dipole moment matrix for v ≤ 9 based on intensity measurements in chemical laser emission.

References

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

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]

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

di Londardo and Douglas, 1973
di Londardo, G.; Douglas, A.E., The electronic spectrum of HF. I. The B¹Σ⁺-X¹Σ⁺ 1 band system, Can. J. Phys., 1973, 51, 434. [all data]

di Lonardo and Douglas, 1972
di Lonardo, G.; Douglas, A.E., Electronic spectra of HF and F₂, J. Chem. Phys., 1972, 56, 5185. [all data]

Johns and Barrow, 1959
Johns, J.W.C.; Barrow, R.F., The ultra-violet spectra of HF and DF, Proc. R. Soc. London A, 1959, 251, 504. [all data]

Safari, 1954
Safari, E., Contribution a l'etude spectrale de l'acide fluorhydrique, Ann. Phys. (Paris), 1954, 9, 203. [all data]

Mann, Thrush, et al., 1961
Mann, D.E.; Thrush, B.A.; Lide, D.R., Jr.; Ball, J.J.; Acquista, N., Spectroscopy of fluorine flames. I. Hydrogen-fluorine flame and the vibration-rotation emission spectrum of HF, J. Chem. Phys., 1961, 34, 420. [all data]

Herget, Deeds, et al., 1962
Herget, W.F.; Deeds, W.E.; Gailar, N.M.; Lovell, R.J.; Nielsen, A.H., Infrared spectrum of hydrogen fluoride: line positions and line shapes. Part II. Treatment of data and results, J. Opt. Soc. Am., 1962, 52, 1113. [all data]

Fishburne and Rao, 1966
Fishburne, E.S.; Rao, K.N., Vibration rotation bands of HF, J. Mol. Spectrosc., 1966, 19, 290. [all data]

Webb and Rao, 1968
Webb, D.U.; Rao, K.N., Vibration rotation bands of heated hydrogen halides, J. Mol. Spectrosc., 1968, 28, 121. [all data]

Rothschild, 1964
Rothschild, W.G., Pure rotational absorption spectrum of hydrogen fluoride vapor between 22 and 250 μ, J. Opt. Soc. Am., 1964, 54, 20. [all data]

Revich and Stankevich, 1966
Revich, V.E.; Stankevich, S.A., The rotational spectra of HF and DF molecules, Dokl. Phys. Chem. Engl. Transl., 1966, 170, 699, In original 1376. [all data]

Mason and Nielsen, 1967
Mason, A.A.; Nielsen, A.H., Rotational spectrum of hydrogen fluoride: frequencies and linewidths, J. Opt. Soc. Am., 1967, 57, 1464. [all data]

Weiss, 1963
Weiss, R., Stark effect and hyperfine structure of hydrogen fluoride, Phys. Rev., 1963, 131, 659. [all data]

Muenter and Klemperer, 1970
Muenter, J.S.; Klemperer, W., Hyperfine structure constants of HF and DF, J. Chem. Phys., 1970, 52, 6033. [all data]

Muenter, 1972
Muenter, J.S., Polarizability anisotropy of hydrogen fluoride, J. Chem. Phys., 1972, 56, 5409. [all data]

de Leeuw and Dymanus, 1973
de Leeuw, F.H.; Dymanus, A., Magnetic properties and molecular quadrupole moment of HF and HCl by molecular-beam electric-resonance spectroscopy, J. Mol. Spectrosc., 1973, 48, 427. [all data]

Baker, Nelson, et al., 1961
Baker, M.R.; Nelson, H.M.; Leavitt, J.A.; Ramsey, N.F., Nuclear magnetic interactions in hydrogen fluoride, Phys. Rev., 1961, 121, 807. [all data]

Fallon, Vanderslice, et al., 1960
Fallon, R.J.; Vanderslice, J.T.; Mason, E.A., Potential energy curves of hydrogen fluoride, J. Chem. Phys., 1960, 32, 698. [all data]

Salama and Hasted, 1976
Salama, A.; Hasted, J.B., Electron energy loss spectrum of hydrogen fluoride, J. Phys. B:, 1976, 9, 333. [all data]

Dunning, 1976
Dunning, T.H., Jr., The low-lying states of hydrogen fluoride: potential energy curves for the X¹Σ⁺, ³Σ⁺, ³Π, and ¹Π states, J. Chem. Phys., 1976, 65, 3854. [all data]

Ogilvie and Koo, 1976
Ogilvie, J.F.; Koo, D., Dunham potential energy coefficients of the hydrogen halides and carbon monoxide, J. Mol. Spectrosc., 1976, 61, 332-336. [all data]

Bondybey, Pearson, et al., 1972
Bondybey, V.; Pearson, P.K.; Schaefer, H.F., III, Theoretical potential energy curves for OH, HF⁺, HF, HF^-, NeH⁺, and NeH, J. Chem. Phys., 1972, 57, 1123. [all data]

Krauss and Neumann, 1974
Krauss, M.; Neumann, D., Multi-configuration self-consistent-field calculation of the dissociation energy and electronic structure of hydrogen fluoride, Mol. Phys., 1974, 27, 917. [all data]

Meyer and Rosmus, 1975
Meyer, W.; Rosmus, P., PNO-Cl and CEPA studies of electron correlation effects. III. Spectroscopic constants and dipole moment functions for the ground states of the first-row and second-row diatomic hydrides, J. Chem. Phys., 1975, 63, 2356. [all data]

Deutsch, 1967
Deutsch, T.F., Laser emission from HF rotational transitions, Appl. Phys. Lett., 1967, 11, 18. [all data]

Mason, von Holle, et al., 1971
Mason, M.G.; von Holle, W.G.; Robinson, D.W., Mid- and far-infrared spectra of HF and DF in rare-gas matrices, J. Chem. Phys., 1971, 54, 3491. [all data]

Walker, Dehmer, et al., 1973
Walker, T.E.H.; Dehmer, P.M.; Berkowitz, J., Rotational band shapes in photoelectron spectroscopy: HF DF, J. Chem. Phys., 1973, 59, 4292. [all data]

Guyon, Spohr, et al., 1976
Guyon, P.-M.; Spohr, R.; Chupka, W.A.; Berkowitz, J., Threshold photoelectron spectra of HF, DF, and F₂, J. Chem. Phys., 1976, 65, 1650-1658. [all data]

Berkowitz, Chupka, et al., 1971
Berkowitz, J.; Chupka, W.A.; Guyon, P.M.; Holloway, J.H.; Spohr, R., Photoionization mass spectrometric study of F₂, HF, and DF, J. Chem. Phys., 1971, 54, 5165. [all data]

Berkowitz, 1971
Berkowitz, J., Experimental potential energy curves for X²{PI} and ²Σ⁺ states of HF⁺, Chem. Phys. Lett., 1971, 11, 21. [all data]

Banna and Shirley, 1975
Banna, M.S.; Shirley, D.A., Molecular photoelectron spectroscopy at 132.3 eV. The second-row hydrides, J. Chem. Phys., 1975, 63, 4759. [all data]

Shaw and Thomas, 1975
Shaw, R.W., Jr.; Thomas, T.D., Auger electron spectrum and ionization potentials of the HF molecule, Phys. Rev. A:, 1975, 11, 1491. [all data]

Naude and Verleger, 1950
Naude, S.M.; Verleger, H., The vibration-rotation bands of the hydrogen halides HF, H³⁵Cl, H³⁷Cl, H⁷⁹Br, H⁸¹Br and H¹²⁷I, Proc. Phys. Soc. London Sect. A, 1950, 63, 470. [all data]

Sileo and Cool, 1976
Sileo, R.N.; Cool, T.A., Overtone emission spectroscopy of HF and DF: vibrational matrix elements and dipole moment function, J. Chem. Phys., 1976, 65, 117. [all data]

Kompa and Pimentel, 1967
Kompa, K.L.; Pimentel, G.C., Hydrofluoric acid chemical laser, J. Chem. Phys., 1967, 47, 857. [all data]

Deutsch, 1967, 2
Deutsch, T.F., Molecular laser action in hydrogen and deuterium halides, Appl. Phys. Lett., 1967, 10, 234. [all data]

Coldhar, Osgood, et al., 1971
Coldhar, J.; Osgood, R.M., Jr.; Javan, A., Observation of intense superradiant emission in the high-gain infrared transitions of HF and DF molecules, Appl. Phys. Lett., 1971, 18, 167. [all data]

Meredith, 1972
Meredith, R.E., Strengths and widths in the first overtone band of hydrogen fluoride, J. Quant. Spectrosc. Radiat. Transfer, 1972, 12, 485. [all data]

Spellicy, Meredith, et al., 1972
Spellicy, R.L.; Meredith, R.E.; Smith, F.G., Strengths and collision broadened widths in the second overtone band of hydrogen fluoride, J. Chem. Phys., 1972, 57, 5119. [all data]

Lie, 1974
Lie, G.C., Study of the theoretical dipole moment function and infrared transition matrix for the X¹Σ⁺ state of the HF molecule, J. Chem. Phys., 1974, 60, 2991. [all data]

Rimpel, 1974
Rimpel, G., Linienstarken in der 4-0- und 5-0-Rotationsschwingungsbande von Fluorwasserstoff, Z. Naturforsch. A, 1974, 29, 588. [all data]

Yardley and Balint-Kurti, 1976
Yardley, R.N.; Balint-Kurti, G.G., Ab initio valence-bond calculations on HF, LiH, LiH⁺ and LiF, Mol. Phys., 1976, 31, 921. [all data]

Hinchen, 1974
Hinchen, J.J., Determination of vibration-rotation line strengths for HF and DF by use of an HF/DF cw laser, J. Opt. Soc. Am., 1974, 64, 1162. [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)

Δ_fH°_gas Enthalpy of formation of gas at standard conditions
Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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S°_{gas,1 bar}	Entropy of gas at standard conditions (1 bar)
Δ_fH°_gas	Enthalpy of formation of gas at standard conditions