cyclopentadienide anion
- Formula: C5H5-
- Molecular weight: 65.0937
- IUPAC Standard InChIKey: SINKOGOPEQSHQD-UHFFFAOYSA-N
- CAS Registry Number: 12127-83-2
- Chemical structure:
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Reaction thermochemistry data
Go To: Top, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled as indicated in comments:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 353.9 ± 2.2 | kcal/mol | G+TS | Bartmess, Scott, et al., 1979 | gas phase; value altered from reference due to change in acidity scale; B |
ΔrH° | 354.9 ± 2.9 | kcal/mol | G+TS | Cumming and Kebarle, 1978 | gas phase; B |
ΔrH° | 357.2 ± 2.0 | kcal/mol | D-EA | Engelking and Lineberger, 1977 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 347.7 ± 2.0 | kcal/mol | IMRE | Bartmess, Scott, et al., 1979 | gas phase; value altered from reference due to change in acidity scale; B |
ΔrG° | 348.7 ± 2.0 | kcal/mol | IMRE | Cumming and Kebarle, 1978 | gas phase; B |
By formula: C5H5- + C5H6 = (C5H5- • C5H6)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | <8.60 | kcal/mol | IMRB | Meot-ner, 1988 | gas phase; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 20. | cal/mol*K | N/A | Meot-ner, 1988 | gas phase; Entropy change calculated or estimated, DG<, ΔrH<; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | <2.6 ± 1.0 | kcal/mol | IMRB | Meot-ner, 1988 | gas phase; B |
Free energy of reaction
ΔrG° (kcal/mol) | T (K) | Method | Reference | Comment |
---|---|---|---|---|
3.6 | 250. | PHPMS | Meot-ner, 1988 | gas phase; Entropy change calculated or estimated, DG<, ΔrH<; M |
( • 2C2D3N) + C2D3N = ( • 3C2D3N)
By formula: (C5H5- • 2C2D3N) + C2D3N = (C5H5- • 3C2D3N)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 10.2 | kcal/mol | PHPMS | Meot-ner, 1988 | gas phase; Entropy change calculated or estimated, ΔrH<, CD3CN; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 22. | cal/mol*K | N/A | Meot-ner, 1988 | gas phase; Entropy change calculated or estimated, ΔrH<, CD3CN; M |
Free energy of reaction
ΔrG° (kcal/mol) | T (K) | Method | Reference | Comment |
---|---|---|---|---|
5.1 | 232. | PHPMS | Meot-ner, 1988 | gas phase; Entropy change calculated or estimated, ΔrH<, CD3CN; M |
By formula: C5H5- + H2O = (C5H5- • H2O)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 11.0 ± 1.0 | kcal/mol | TDAs | Meot-ner, 1988 | gas phase; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 16.1 | cal/mol*K | PHPMS | Meot-ner, 1988 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 6.2 ± 1.0 | kcal/mol | TDAs | Meot-ner, 1988 | gas phase; B |
By formula: C5H5- + C7H8O = (C5H5- • C7H8O)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 19.2 ± 1.0 | kcal/mol | TDAs | Meot-ner, 1988 | gas phase; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 29.8 | cal/mol*K | PHPMS | Meot-ner, 1988 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 10.3 ± 1.0 | kcal/mol | TDAs | Meot-ner, 1988 | gas phase; B |
By formula: C5H5- + C2H3F3O = (C5H5- • C2H3F3O)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 20.6 ± 1.0 | kcal/mol | TDAs | Meot-ner, 1988 | gas phase; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 24.3 | cal/mol*K | PHPMS | Meot-ner, 1988 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 13.3 ± 1.0 | kcal/mol | TDAs | Meot-ner, 1988 | gas phase; B |
By formula: C5H5- + C3H6O = (C5H5- • C3H6O)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 13.5 ± 1.0 | kcal/mol | TDAs | Meot-ner, 1988 | gas phase; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 21.8 | cal/mol*K | PHPMS | Meot-ner, 1988 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 7.0 ± 1.0 | kcal/mol | TDAs | Meot-ner, 1988 | gas phase; B |
By formula: C5H5- + C4H10O = (C5H5- • C4H10O)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 17.0 ± 1.0 | kcal/mol | TDAs | Meot-ner, 1988 | gas phase; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 32.0 | cal/mol*K | PHPMS | Meot-ner, 1988 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 7.4 ± 1.0 | kcal/mol | TDAs | Meot-ner, 1988 | gas phase; B |
( • C2D3N) + C2D3N = ( • 2C2D3N)
By formula: (C5H5- • C2D3N) + C2D3N = (C5H5- • 2C2D3N)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 13.1 | kcal/mol | PHPMS | Meot-ner, 1988 | gas phase; CD3CN; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 22.8 | cal/mol*K | PHPMS | Meot-ner, 1988 | gas phase; CD3CN; M |
By formula: C5H5- + CH4O = (C5H5- • CH4O)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 13.2 ± 1.0 | kcal/mol | TDAs | Meot-ner, 1988 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 6.9 ± 1.0 | kcal/mol | TDAs | Meot-ner, 1988 | gas phase; B |
By formula: C5H5- + C2H3N = (C5H5- • C2H3N)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 15.5 ± 1.0 | kcal/mol | TDAs | Meot-ner, 1988 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 8.7 ± 1.0 | kcal/mol | TDAs | Meot-ner, 1988 | gas phase; B |
By formula: (C5H5- • H2O) + H2O = (C5H5- • 2H2O)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 10.0 | kcal/mol | PHPMS | Meot-ner, 1988 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 17.4 | cal/mol*K | PHPMS | Meot-ner, 1988 | gas phase; M |
By formula: (C5H5- • C3H6O) + C3H6O = (C5H5- • 2C3H6O)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 9.8 | kcal/mol | PHPMS | Meot-ner, 1988 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 16.4 | cal/mol*K | PHPMS | Meot-ner, 1988 | gas phase; M |
By formula: C5H5- + C2D3N = (C5H5- • C2D3N)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 15.5 | kcal/mol | PHPMS | Meot-ner, 1988 | gas phase; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 22.8 | cal/mol*K | PHPMS | Meot-ner, 1988 | gas phase; M |
By formula: C5H5- + CCoO = C6H5CoO-
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 10.20 ± 0.80 | kcal/mol | N/A | Sunderlin and Squires, 1999 | gas phase; B |
+ = C5H5Co-
By formula: C5H5- + Co = C5H5Co-
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 7.00 ± 0.60 | kcal/mol | N/A | Sunderlin and Squires, 1999 | gas phase; B |
References
Go To: Top, Reaction thermochemistry data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
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]
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]
Engelking and Lineberger, 1977
Engelking, P.C.; Lineberger, W.C.,
Laser photoelectron spectrometry of C5H5-: A determination of the electron affinity and Jahn-Teller coupling in cyclopentadienyl,
J. Chem. Phys., 1977, 67, 1412. [all data]
Meot-ner, 1988
Meot-ner, M.,
The Ionic Hydrogen Bond and Solvation. 7. Interaction Energies of Carbanions with Solvent Molecules,
J. Am. Chem. Soc., 1988, 110, 12, 3858, https://doi.org/10.1021/ja00220a022
. [all data]
Sunderlin and Squires, 1999
Sunderlin, L.S.; Squires, R.R.,
Bond strengths in cyclopentadienyl metal carbonyl anions,
Int. J. Mass Spectrom., 1999, 183, 149-161, https://doi.org/10.1016/S1387-3806(98)14230-6
. [all data]
Notes
Go To: Top, Reaction thermochemistry data, References
- Symbols used in this document:
T Temperature ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions ΔrS° Entropy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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