Mercapto radical

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Gas phase thermochemistry data

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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
Δfgas139.33kJ/molReviewChase, 1998Data last reviewed in June, 1977
Quantity Value Units Method Reference Comment
gas,1 bar195.63J/mol*KReviewChase, 1998Data last reviewed in June, 1977

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 (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/mol*K)
    t = temperature (K) / 1000.

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View table.

Temperature (K) 298. - 1200.1200. - 6000.
A 38.0430632.99507
B -27.467922.841514
C 34.06462-0.507766
D -11.798750.038247
E -0.009743-2.909667
F 128.8961124.4870
G 248.3945230.0066
H 139.3272139.3272
ReferenceChase, 1998Chase, 1998
Comment Data last reviewed in June, 1977 Data last reviewed in June, 1977

Reaction thermochemistry data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: John E. Bartmess

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

S- + Hydrogen cation = Mercapto radical

By formula: S- + H+ = HS

Quantity Value Units Method Reference Comment
Δr1465.03 ± 0.29kJ/molD-EABlondel, Chaibi, et al., 2005gas phase; (32)S: 2.0771040(9) eV: revised analysis of Blondel, Delsart, et al., 2001
Δr1465. ± 12.kJ/molEndoRempala and Ervin, 2000gas phase
Quantity Value Units Method Reference Comment
Δr1441.8 ± 0.79kJ/molH-TSBlondel, Chaibi, et al., 2005gas phase; (32)S: 2.0771040(9) eV: revised analysis of Blondel, Delsart, et al., 2001
Δr1442. ± 13.kJ/molH-TSRempala and Ervin, 2000gas phase

Gas phase ion energetics data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data evaluated as indicated in comments:
L - Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
LL - Sharon G. Lias and Joel F. Liebman
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

View reactions leading to HS+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
IE (evaluated)10.422 ± 0.001eVN/AN/AL
Quantity Value Units Method Reference Comment
Δf(+) ion1143. ± 4.kJ/molN/AN/A 
Quantity Value Units Method Reference Comment
ΔfH(+) ion,0K1143. ± 4.kJ/molN/AN/A 

Electron affinity determinations

EA (eV) Method Reference Comment
2.31473LPESChaibi, Delsart, et al., 2006For H(32)S-. Given: 2.3147282(17) eV; B
2.3170 ± 0.0020LPESBreyer, Frey, et al., 1981B
2.326 ± 0.091D-EABartmess, Scott, et al., 1979value altered from reference due to change in acidity scale; B
2.32085D-EAShiell, Hu, et al., 19000K:350.125±0.009 kcal/mol, corr to 298K from Gurvich, Veyts, et al., With EA( Breyer, Frey, et al., 1981)BDE(0K)=89.97±0.05; B
2.3140 ± 0.0030LPDJanousek and Brauman, 1981B
2.3016 ± 0.0013LPDEyler and Atkinson, 1974B
2.319 ± 0.010PDSteiner, 1968B
2.19422R-ARefaey, 1976B
2.31521N/ACheck, Faust, et al., 2001MnO2-(t); ; ΔS(EA)=5.4; B
2.298 ± 0.039SIPage and Goode, 1969The Magnetron method, lacking mass analysis, is not considered reliable.; B

Ionization energy determinations

IE (eV) Method Reference Comment
10.4219TEMilan, Buma, et al., 1996LL
10.4219 ± 0.0004TEHsu, Baldwin, et al., 1994LL
10.40 ± 0.01ENDSmith, Adams, et al., 1981LLK
10.43EVALHuber and Herzberg, 1979LLK
10.37 ± 0.01PEDunlavey, Dyke, et al., 1979LLK
10.41 ± 0.03SMorrow, 1966RDSH
10.5 ± 0.1EIPalmer and Lossing, 1962RDSH

De-protonation reactions

S- + Hydrogen cation = Mercapto radical

By formula: S- + H+ = HS

Quantity Value Units Method Reference Comment
Δr1465.03 ± 0.29kJ/molD-EABlondel, Chaibi, et al., 2005gas phase; (32)S: 2.0771040(9) eV: revised analysis of Blondel, Delsart, et al., 2001; B
Δr1465. ± 12.kJ/molEndoRempala and Ervin, 2000gas phase; B
Quantity Value Units Method Reference Comment
Δr1441.8 ± 0.79kJ/molH-TSBlondel, Chaibi, et al., 2005gas phase; (32)S: 2.0771040(9) eV: revised analysis of Blondel, Delsart, et al., 2001; B
Δr1442. ± 13.kJ/molH-TSRempala and Ervin, 2000gas phase; B

Anion protonation reactions

HS- + Hydrogen cation = Hydrogen sulfide

By formula: HS- + H+ = H2S

Quantity Value Units Method Reference Comment
Δr1470. ± 3.kJ/molAVGN/AAverage of 6 out of 7 values; Individual data points
Quantity Value Units Method Reference Comment
Δr1441. ± 13.kJ/molH-TSRempala and Ervin, 2000gas phase; B
Δr1443. ± 8.4kJ/molIMREBartmess, Scott, et al., 1979gas phase; value altered from reference due to change in acidity scale; B
Δr1443.1 ± 0.42kJ/molH-TSShiell, Hu, et al., 1900gas phase; 0K:350.125±0.009 kcal/mol, corr to 298K from Gurvich, Veyts, et al., With EA( Breyer, Frey, et al., 1981)BDE(0K)=89.97±0.05; B
Δr1446. ± 8.4kJ/molIMRECumming and Kebarle, 1978gas phase; B
Δr1432.2kJ/molN/ACheck, Faust, et al., 2001gas phase; MnO2-(t); ; ΔS(EA)=5.4; B

Constants of diatomic molecules

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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, 1977

Symbols used in the table of constants
SymbolMeaning
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)
Diatomic constants for 32S1H
StateTeωeωexeωeyeBeαeγeDeβereTrans.ν00
H 2Δ     [9.46]     [1.351] H ← X 80847.5 1
Morrow, 1966
G 2Δ     [9.01]     [1.384] G ← X 79343.3 1
Morrow, 1966
F 2Δ     [9.19]     [1.370] F ← X 76707.9 1
Morrow, 1966
E 2Σ     [9.076]     [1.3788] E ← X 71317.7 1
Morrow, 1966
StateTeωeωexeωeyeBeαeγeDeβereTrans.ν00
D 2Δ     [9.215]   [6.1E-4]  [1.3684] D ← X 71194.72 1
Morrow, 1966
C 2Δ 2          C ← X (64060)
Morrow, 1966
B 2Σ (59641) [2557.03] Z (56.8) 3  8.785 0.259  [8.2E-4]  1.4014 B ← X R 59621.71 Z
Morrow, 1966
A 2Σ+ (31038) 1979.8 Z 97.65  8.521 4 5 0.464 -0.022 6.36E-4 6.0E-5 1.4230 A ↔ X 6 R 30662.42 Z
missing citation; missing citation; Pathak and Palmer, 1969
StateTeωeωexeωeyeBeαeγeDeβereTrans.ν00
X 2Πi 0 7 (2711.6) 8 (59.9) 8  [9.4611] 9 (0.270) 8  [4.80E-4]  1.3409 10  
Acquista and Schoen, 1970
          11  
Meerts and Dymanus, 1974; Meerts and Dymanus, 1975
          12  
McDonald, 1963; Radford and Linzer, 1963; Uehara and Morino, 1970; Brown and Thistlethwaite, 1972; Tanimoto and Uehara, 1973

Notes

1The v00 values refer to the zero-point of the Hill-Van Vleck expression for the lower state and are exclusive of the J independent terms -BΛ2 in the upper states, contrary to definitions normally adopted in these tables. Only the X 2Π3/2 subbands have been observed.
2Weak diffuse band near 1561 ; sharper in SD.
3From isotope shifts.
4Spin-splitting constant γ0 = +0.313.
5The rotational lines of bands having v'≥1 are increasingly diffuse.
6Observed in absorption (flash photolysis of H2S and D2S) by Ramsay, 1952, Johns and Ramsay, 1961, in matrix absorption by Acquista and Schoen, 1970, and in emission by Leach, 1950, Pathak and Palmer, 1969. Franck-Condon factors Nicholls, Fraser, et al., 1960.
7A0 = -376.96 Ramsay, 1952. On the basis of certain higher order corrections Veseth, 1971 gives A0 = -378.53 Veseth, 1971 (and B0 = 9.465, D0 = 4.7E-4).
8From the constants for SD Pathak and Palmer, 1969.
9Λ-doubling and hfs parameters Meerts and Dymanus, 1975.
10Vibration sp. 16
11Hf Λ-doubling sp. 17 18
12EPR sp. 19
13From an extrapolation of the vibrational levels of A 2Σ+ to the limit 1D + 2S Johns and Ramsay, 1961; consistent with the observed predissociation in A 2Σ+. Photoionization mass-spectrometry of H2S Dibeler and Liston, 1968 gives D00C(S1H) = 3.67 eV (recalculated using updated auxilliary data). See also Meyer and Rosmus, 1975.
14Both D00 and I.P. refer to the lowest existing molecular level, in agreement with definitions but contrary to the values given by Johns and Ramsay, 1961 and Morrow, 1966, respectively, which refer to the zero-point of the Hill-Van Vleck expression for the ground state.
15Extrapolation of a short Rydberg series Morrow, 1966.
16In argon matrices at 20.4 K.
17Molecular beam electric resonance study. The strongest Λ-doubling transitions in 2Π3/2, J=3/2 occur at 111.4862 (F=1-1) and 111.5452 MHz (F=2-2), in J=5/2 at 442.4781(F=2-2) and 442.6277 MHz (F=3-3); these observations supersede earlier predictions Radford and Linzer, 1963, Brown and Thistlethwaite, 1972, Tanimoto and Uehara, 1973 from EPR measurements.
18μel(v=0) = 0.7580 D Meerts and Dymanus, 1974, Meerts and Dymanus, 1975. Stark effect in EPR spectrum Carrington, Levy, et al., 1967, Byfleet, Carrington, et al., 1971 yields the less accurate value 0.62 D. Predicted dipole moment function Meyer and Rosmus, 1975. Theoretical charge distributions Cade, Bader, et al., 1969.
19For the EPR spectrum of 33SH and 33S hf interaction see Miller, 1971.
20Large electronic isotope shift.
21Spin splitting constant γ0 = +0.163. The lines of the 2-0 absorption band are diffuse.
22A0 = -376.75 Ramsay, 1952. Taking into account higher order corrections Veseth, 1971 derives A0 = -378.32 Veseth, 1971 (and B0 = 4.899, D0 = 1.3E-4).
23Estimates by Ramsay, 1952 and Pathak and Palmer, 1969.
24μel(v=0) = 0.7571 D Meerts and Dymanus, 1975.

References

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Constants of diatomic molecules, NIST Free Links, 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]

Blondel, Chaibi, et al., 2005
Blondel, C.; Chaibi, W.; Delsart, C.; Drag, C.; Goldfarb, F.; Kroger, S., The electron affinities of O, Si, and S revisited with the photodetachment microscope, Eur. Phys. J. D, 2005, 33, 3, 335-342, https://doi.org/10.1140/epjd/e2005-00069-9 . [all data]

Blondel, Delsart, et al., 2001
Blondel, C.; Delsart, C.; Goldfarb, F., Electron spectrometry at the mu eV level and the electron affinities of Si and F, J. Phys. B: Atom. Mol. Opt. Phys., 2001, 34, 9, L281-L288, https://doi.org/10.1088/0953-4075/34/9/101 . [all data]

Rempala and Ervin, 2000
Rempala, K.; Ervin, K.M., Collisional activation of the Endoergic Hydrogen Atom Transfer Reaction S-(2P) + H2 - SH- + H, J. Chem. Phys., 2000, 112, 10, 4579, https://doi.org/10.1063/1.481016 . [all data]

Chaibi, Delsart, et al., 2006
Chaibi, W.; Delsart, C.; Drag, C.; Blondel, C., High precision measurement of the (SH)-S-32 electron affinity by laser detachment microscopy, J. Molec. Spectros., 2006, 239, 1, 11-15, https://doi.org/10.1016/j.jms.2006.05.012 . [all data]

Breyer, Frey, et al., 1981
Breyer, F.; Frey, P.; Hotop, H., High Resolution Photoelectron Spectrometry of Negative Ions: Rotational Transitions in Laser-Photodetachment of OH-, SH-, and SD-, Z. Phys. A, 1981, 300, 1, 7, https://doi.org/10.1007/BF01412609 . [all data]

Bartmess, Scott, et al., 1979
Bartmess, J.E.; Scott, J.A.; McIver, R.T., Jr., The gas phase acidity scale from methanol to phenol, J. Am. Chem. Soc., 1979, 101, 6047. [all data]

Shiell, Hu, et al., 1900
Shiell, R.C.; Hu, X.K.; Hu, Q.J.; Hepburn, J.W., A determination of the bond dissociation energy (D-0(H-SH)): Threshold ion-pair production spectroscopy (TIPPS) of a triatomic molecule, J. Phys. Chem. A, 1900, 104, 19, 4339-4342, https://doi.org/10.1021/jp000025k . [all data]

Gurvich, Veyts, et al.
Gurvich, L.V.; Veyts, I.V.; Alcock, C.B., Hemisphere Publishing, NY, 1989, V. 1 2, Thermodynamic Properties of Individual Substances, 4th Ed. [all data]

Janousek and Brauman, 1981
Janousek, B.K.; Brauman, J.I., Electron Photodetachment from HS-. The Electron Affinity of HS, Phys. Rev. A, 1981, 23, 4, 1673, https://doi.org/10.1103/PhysRevA.23.1673 . [all data]

Eyler and Atkinson, 1974
Eyler, J.R.; Atkinson, G.H., Dye laser-induced photodetachment of electrons from SH- studied by ICR spectroscopy, Chem. Phys. Lett., 1974, 28, 217. [all data]

Steiner, 1968
Steiner, B., Photodetachment of Electrons From SH-, J. Chem. Phys., 1968, 49, 11, 5097, https://doi.org/10.1063/1.1670004 . [all data]

Refaey, 1976
Refaey, K.M.A., Endoergic ion-molecule-collision processes of negative ions. II. Collisions of I- on H2S, CS2, and COS, J. Chem. Phys., 1976, 65, 2002. [all data]

Check, Faust, et al., 2001
Check, C.E.; Faust, T.O.; Bailey, J.M.; Wright, B.J.; Gilbert, T.M.; Sunderlin, L.S., Addition of Polarization and Diffuse Functions to the LANL2DZ Basis Set for P-Block Elements, J. Phys. Chem. A,, 2001, 105, 34, 8111, https://doi.org/10.1021/jp011945l . [all data]

Page and Goode, 1969
Page, F.M.; Goode, G.C., Negative Ions and the Magnetron., Wiley, NY, 1969. [all data]

Milan, Buma, et al., 1996
Milan, J.B.; Buma, W.J.; deLange, C.A., Zero-kinetic-energy pulsed-field ionization spectroscopy of the a 1δ state of SH+ (CD+), J. Chem. Phys., 1996, 104, 521. [all data]

Hsu, Baldwin, et al., 1994
Hsu, C.-W.; Baldwin, D.P.; Liao, C.-L.; Ng, C.Y., Rotationally resolved nonresonant two-photon ionization of SH, J. Chem. Phys., 1994, 100, 8047. [all data]

Smith, Adams, et al., 1981
Smith, D.; Adams, N.G.; Lindinger, W., Reactions of the HnS ions (n = 0 to 3) with several molecular gases at thermal energies, J. Chem. Phys., 1981, 75, 3365. [all data]

Huber and Herzberg, 1979
Huber, K.P.; Herzberg, G., Molecular Spectra and Molecular Structure. IV. Constants of Diatomic Molecules,, Van Nostrand Reinhold Co., 1979, ,1. [all data]

Dunlavey, Dyke, et al., 1979
Dunlavey, S.; Dyke, J.; Fayad, N.; Jonathan, N.; Morris, A., Vacuum ultraviolet photoelectron spectroscopy of transient species. Part 10. The SH(X2çi) radical and the S(3P) atom, Mol. Phys., 1979, 38, 729. [all data]

Morrow, 1966
Morrow, B.A., The absorption spectrum of SH and SD in the vacuum ultraviolet, Can. J. Phys., 1966, 44, 2447. [all data]

Palmer and Lossing, 1962
Palmer, T.F.; Lossing, F.P., Free radicals by mass spectrometry. XXVIII. The HS, CH3S, and phenyl-S radicals: ionization potentials and heats of formation, J. Am. Chem. Soc., 1962, 84, 4661. [all data]

Cumming and Kebarle, 1978
Cumming, J.B.; Kebarle, P., Summary of gas phase measurements involving acids AH. Entropy changes in proton transfer reactions involving negative ions. Bond dissociation energies D(A-H) and electron affinities EA(A), Can. J. Chem., 1978, 56, 1. [all data]

Pathak and Palmer, 1969
Pathak, C.M.; Palmer, H.B., Chemical excitation of the A2Σ+-X2Π system of SH and SD, J. Mol. Spectrosc., 1969, 32, 157. [all data]

Acquista and Schoen, 1970
Acquista, N.; Schoen, L.J., Matrix isolation spectrum of the SH radical, J. Chem. Phys., 1970, 53, 1290. [all data]

Meerts and Dymanus, 1974
Meerts, W.L.; Dymanus, A., The hyperfine Λ-doubling spectrum of sulfur hydride in the 2Π3/2 state, Astrophys. J., 1974, 187, 45. [all data]

Meerts and Dymanus, 1975
Meerts, W.L.; Dymanus, A., A molecular beam electric resonance study of the hyperfine Λ doubling spectrum of OH, OD, SH, and SD, Can. J. Phys., 1975, 53, 2123. [all data]

McDonald, 1963
McDonald, C.C., EPR spectra of SH, SD, and SO radicals in the gaseous state, J. Chem. Phys., 1963, 39, 2587. [all data]

Radford and Linzer, 1963
Radford, H.E.; Linzer, M., Radio spectrum of SH, Phys. Rev. Lett., 1963, 10, 443. [all data]

Uehara and Morino, 1970
Uehara, H.; Morino, Y., Gas-phase EPR spectra of rotationally excited states of SH and ClO free radicals, J. Mol. Spectrosc., 1970, 36, 158. [all data]

Brown and Thistlethwaite, 1972
Brown, J.M.; Thistlethwaite, P.J., A measurment of the λ-doubling transition frequencies for SH in its second rotational level, Mol. Phys., 1972, 23, 635. [all data]

Tanimoto and Uehara, 1973
Tanimoto, M.; Uehara, H., Proton hyperfine interactions in the gas-phase E.P.R. spectra of SH (2Π3/2) in two lowest rotational levels, Mol. Phys., 1973, 25, 1193. [all data]

Ramsay, 1952
Ramsay, D.A., Absorption spectra of SH and SD produced by flash photolysis of H2S and D2S, J. Chem. Phys., 1952, 20, 1920. [all data]

Johns and Ramsay, 1961
Johns, J.W.C.; Ramsay, D.A., The absorption spectrum and dissociation energy of SH, Can. J. Phys., 1961, 39, 210. [all data]

Leach, 1950
Leach, M.S., Sur les spectres d'emission de l'hydrogene sulfure excites par chocs electroniques. Spectre d'emission du radical SH, Compt. Rend., 1950, 230, 2181. [all data]

Nicholls, Fraser, et al., 1960
Nicholls, R.W.; Fraser, P.A.; Jarmain, W.R.; McEachran, R.P., Vibrational transition probabilities of diatomic molecules: collected results. IV. BeO, BO, CH+, CO, NO, SH, O2, O2+, Astrophys. J., 1960, 131, 399. [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]

Dibeler and Liston, 1968
Dibeler, V.H.; Liston, S.K., Mass-spectrometric study of photoionization. XI.Hydrogen sulfide and sulfur dioxide, J. Chem. Phys., 1968, 49, 482. [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]

Carrington, Levy, et al., 1967
Carrington, A.; Levy, D.H.; Miller, T.A., Stark effect in gas-phase electron resonance. The dipole moments of ClO, BrO, SH, and 1ΔSO, J. Chem. Phys., 1967, 47, 3801. [all data]

Byfleet, Carrington, et al., 1971
Byfleet, C.R.; Carrington, A.; Russell, D.K., Electric dipole moments of open-shell diatomic molecules, Mol. Phys., 1971, 20, 271. [all data]

Cade, Bader, et al., 1969
Cade, P.E.; Bader, R.F.W.; Henneker, W.H.; Keaveny, I., Molecular charge distributions and chemical binding. IV. The second-row diatomic hydrides AH, J. Chem. Phys., 1969, 50, 5313. [all data]

Miller, 1971
Miller, T.A., Sulfur-33 hyperfine interactions in the gas-phase electron resonance spectra of 2Π SH and 1Δ SO, J. Chem. Phys., 1971, 54, 1658. [all data]


Notes

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