Methane, diazo-
- Formula: CH2N2
- Molecular weight: 42.0400
- IUPAC Standard InChI: InChI=1S/CH2N2/c1-3-2/h1H2
- IUPAC Standard InChIKey: YXHKONLOYHBTNS-UHFFFAOYSA-N
- CAS Registry Number: 334-88-3
- 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: Azimethylene; Diazomethane; Acomethylene; Diazirine; Diazonium methylide
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Gas phase ion energetics 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 evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias
Data compiled as indicated in comments:
B - John E. Bartmess
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 CH2N2+ (ion structure unspecified)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| IE (evaluated) | 8.999 ± 0.001 | eV | N/A | N/A | L |
| Quantity | Value | Units | Method | Reference | Comment |
| Proton affinity (review) | 205.3 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
| Quantity | Value | Units | Method | Reference | Comment |
| Gas basicity | 197.6 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
| IE (eV) | Method | Reference | Comment |
|---|---|---|---|
| 9.00 | PE | Bastide and Maier, 1976 | LLK |
| 8.999 ± 0.001 | S | Merer, 1964 | RDSH |
| 9.03 ± 0.05 | EI | Paulett and Ettinger, 1963 | RDSH |
| 9.2 ± 0.3 | EI | Berkowitz and Wexler, 1962 | RDSH |
Appearance energy determinations
| Ion | AE (eV) | Other Products | Method | Reference | Comment |
|---|---|---|---|---|---|
| CHN2+ | 14.8 ± 0.1 | H | EI | Paulett and Ettinger, 1963 | RDSH |
| CH2+ | 12.3 ± 0.1 | N2 | EI | Paulett and Ettinger, 1963 | RDSH |
De-protonation reactions
CHN2- + =
By formula: CHN2- + H+ = CH2N2
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 371.4 ± 2.2 | kcal/mol | G+TS | Clifford, Wenthold, et al., 1998 | gas phase; Lit values of DfH(H2CNN) range from 71 (78BEN) to 51 ( Laufer and Okabe, 1972). Here we use the computational ( Dixon, de Jong, et al., 2005) agreeing with G3MP2B3; B |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 364.1 ± 2.0 | kcal/mol | IMRE | Clifford, Wenthold, et al., 1998 | gas phase; Lit values of DfH(H2CNN) range from 71 (78BEN) to 51 ( Laufer and Okabe, 1972). Here we use the computational ( Dixon, de Jong, et al., 2005) agreeing with G3MP2B3; B |
| ΔrG° | 365.0 ± 4.0 | kcal/mol | IMRB | DePuy, Van Doren, et al., 1989 | gas phase; Near HF, between H2O2 & acetone. G2 calculations( Gordon and Kass, 1997) give ΔHf(CH2N2)=63.1 kcal/mol; B |
References
Go To: Top, Gas phase ion energetics data, Notes
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]
Bastide and Maier, 1976
Bastide, J.; Maier, J.P.,
Electronic states of the radical cations of the 1,3-dipoles: HCNO, CH2N2, and N3H, studied by photoelectron spectroscopy,
Chem. Phys., 1976, 12, 177. [all data]
Merer, 1964
Merer, A.J.,
The vacuum ultraviolet absorption spectrum of diazomethane,
Can. J. Phys., 1964, 42, 1242. [all data]
Paulett and Ettinger, 1963
Paulett, G.S.; Ettinger, R.,
Mass spectra and appearance potentials of diazirine and diazomethane,
J. Chem. Phys., 1963, 39, 825. [all data]
Berkowitz and Wexler, 1962
Berkowitz, J.; Wexler, S.,
On the ionization potential of the CH2 radical,
J. Chem. Phys., 1962, 37, 1476. [all data]
Clifford, Wenthold, et al., 1998
Clifford, E.P.; Wenthold, P.G.; Lineberger, W.C.; Peterssom, G.A.; Broaddus, K.M.; Kass, S.R.; Kato, S.,
Properties of Diazocarbene [CNN] and the diazomethyl Radical [HCNN] via Ion Chemistry and Spectroscopy,
J. Phys. Chem. A, 1998, 102, 36, 7100, https://doi.org/10.1021/jp9802735
. [all data]
Laufer and Okabe, 1972
Laufer, A.H.; Okabe, H.,
J. Phys. Chem., 1972, 76, 3504. [all data]
Dixon, de Jong, et al., 2005
Dixon, D.A.; de Jong, W.A.; Peterson, K.A.; McMahon, T.B.,
Methyl cation affinities of rare gases and nitrogen and the heat of formation of diazomethane,
J. Phys. Chem. A, 2005, 109, 18, 4073-4080, https://doi.org/10.1021/jp044561e
. [all data]
DePuy, Van Doren, et al., 1989
DePuy, C.H.; Van Doren, J.M.; Gronert, S.; Kass, S.R.; Motell, E.L.; Ellison, G.B.; Bierbaum, V.M.,
Gas-Phase Negative-Ion Chemistry of Diazomethane,
J. Org. Chem., 1989, 54, 8, 1846, https://doi.org/10.1021/jo00269a020
. [all data]
Gordon and Kass, 1997
Gordon, M.S.; Kass, S.R.,
CHN2-: A biradical anion and a potentially new type of reactive intermediate (vol 99, pg 6548, 1995),
J. Phys. Chem. A, 1997, 101, 42, 7922-7922, https://doi.org/10.1021/jp972321b
. [all data]
Notes
Go To: Top, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy IE (evaluated) Recommended ionization energy ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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