4-Aminobenzoic acid

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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:
HL - Edward P. Hunter and Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
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

View reactions leading to C7H7NO2+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
Proton affinity (review)864.7kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity832.3kJ/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
8.3EITobita, Tajima, et al., 1984LBLHLM
7.8PEMeeks, Wahlborg, et al., 1981LLK
8.4 ± 0.2EIBenoit, 1973LLK
8.4PEMeeks, Wahlborg, et al., 1981Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C6H6N+14.8 ± 0.2CO+OHEIBenoit, 1973LLK
C7H6NO+12.1 ± 0.2OHEIBenoit, 1973LLK

De-protonation reactions

C7H6NO2- + Hydrogen cation = 4-Aminobenzoic acid

By formula: C7H6NO2- + H+ = C7H7NO2

Quantity Value Units Method Reference Comment
Δr1437. ± 8.8kJ/molG+TSKebarle and McMahon, 1977gas phase; B
Quantity Value Units Method Reference Comment
Δr1407. ± 8.4kJ/molIMREKebarle and McMahon, 1977gas phase; B

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director


Mass spectrum (electron ionization)

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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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Mass spectrum
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Additional Data

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Owner NIST Mass Spectrometry Data Center
Collection (C) 2014 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin NIST Mass Spectrometry Data Center, 1990.
NIST MS number 118372

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UV/Visible spectrum

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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: Victor Talrose, Eugeny B. Stern, Antonina A. Goncharova, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

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UVVis spectrum
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Additional Data

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Source Grammaticakis, 1951
Owner INEP CP RAS, NIST OSRD
Collection (C) 2007 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin INSTITUTE OF ENERGY PROBLEMS OF CHEMICAL PHYSICS, RAS
Source reference RAS UV No. 409
Instrument n.i.g.
Melting point 188.5

Gas Chromatography

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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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Normal alkane RI, non-polar column, custom temperature program

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Column type Active phase I Reference Comment
OtherMethyl Silicone1547.Ardrey and Moffat, 1981Program: not specified

References

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

Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G., Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update, J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018 . [all data]

Tobita, Tajima, et al., 1984
Tobita, S.; Tajima, S.; Tsuchiya, T., The substituent effect on the single and double hydrogen atom transfer reactions in para-substituted benzoic acid isobutyl esters, Org. Mass Spectrom., 1984, 19, 326. [all data]

Meeks, Wahlborg, et al., 1981
Meeks, J.; Wahlborg, A.; McGlynn, S.P., Photoelectron spectroscopy of carbonyls: Benzoic acid and its derivatives, J. Electron Spectrosc. Relat. Phenom., 1981, 22, 43. [all data]

Benoit, 1973
Benoit, F., Substituent effects in mass spectrometry. III. Substituent effects in the dissociation of the molecular ions of para and meta subtituted benzoic acids, Org. Mass Spectrom., 1973, 7, 295. [all data]

Kebarle and McMahon, 1977
Kebarle, P.; McMahon, T.B., Intrinsic Acidities of Substituted Phenols and Benzoic Acids Determined by Gas Phase Proton Transfer Equilibria, J. Am. Chem. Soc., 1977, 99, 7, 2222, https://doi.org/10.1021/ja00449a032 . [all data]

Grammaticakis, 1951
Grammaticakis, P., Contribution a l'etude de l'absorption dans l'ultraviolet moyen et le visible des arylamines isomeres et de leurs derives N substitues (Premier memoire), Bull. Soc. Chim. Fr., 1951, 18, 220-226. [all data]

Ardrey and Moffat, 1981
Ardrey, R.E.; Moffat, A.C., Gas-liquid chromatographic retention indices of 1318 substances of toxicological interest on SE-30 or OV-1 stationary phase, J. Chromatogr., 1981, 220, 3, 195-252, https://doi.org/10.1016/S0021-9673(00)81925-1 . [all data]


Notes

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