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Methylene, difluoro-

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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.

Data compiled as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Quantity Value Units Method Reference Comment
Deltafgas-182.00kJ/molReviewChase, 1998Data last reviewed in June, 1970
Deltafgas-172. ± 8.4kJ/molEqkEhlert, 1969ALS
Quantity Value Units Method Reference Comment
gas,1 bar240.83J/mol*KReviewChase, 1998Data last reviewed in June, 1970

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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Temperature (K) 298. - 600.600. - 6000.
A 8.82577259.34753
B 125.3652-2.317176
C -129.49400.890518
D 50.33101-0.055879
E 0.259749-3.467545
F -188.2917-209.6155
G 220.9081298.2569
H -182.0040-182.0040
ReferenceChase, 1998Chase, 1998
Comment Data last reviewed in June, 1970 Data last reviewed in June, 1970

Reaction thermochemistry data

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

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

(CF3- bullet 4294967295Methylene, difluoro-) + Methylene, difluoro- = CF3-

By formula: (CF3- bullet 4294967295CF2) + CF2 = CF3-

Quantity Value Units Method Reference Comment
Deltar208. ± 10.kJ/molN/ADeyerl, Alconcel, et al., 2001gas phase; Adiabatic EA, from vibrational structure of spectrum
Deltar213. ± 12.kJ/molN/ABartmess, Scott, et al., 1979gas phase; Paulino and Squires, 1991 suggests that this acidity may be too weak by ca. 5 kcal/mol. However, G2 calcn(JEB) give «DELTA»Hacid=379.9, «DELTA»Gacid=372.0; value altered from reference due to change in acidity scale
Deltar234. ± 11.kJ/molCIDTPaulino and Squires, 1991gas phase; Neutral heat is based on a fluoroform acidity that may be too weak by up to 5 kcal/mol

(CAS Reg. No. 53959-80-1 bullet 4294967295Methylene, difluoro-) + Methylene, difluoro- = CAS Reg. No. 53959-80-1

By formula: (CAS Reg. No. 53959-80-1 bullet 4294967295CF2) + CF2 = CAS Reg. No. 53959-80-1

Quantity Value Units Method Reference Comment
Deltar<33.5kJ/molCIDTPaulino and Squires, 1991, 2gas phase; Probably CF2..Cl-, non-covalent.

References

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, 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]

Ehlert, 1969
Ehlert, T.C., Bonding in C1 and C2 fluroides, J. Phys. Chem., 1969, 73, 949-953. [all data]

Deyerl, Alconcel, et al., 2001
Deyerl, H.J.; Alconcel, L.S.; Continetti, R.E., Photodetachment imaging studies of the electron affinity of CF3, J. Phys. Chem. A, 2001, 105, 3, 552-557, https://doi.org/10.1021/jp003137k . [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]

Paulino and Squires, 1991
Paulino, J.A.; Squires, R.R., Carbene Thermochemistry from Collision-Induced Dissociation Threshold Energy Measurements - The Heats of Formation of X1A1 CF2 and X1A1 CCl2, J. Am. Chem. Soc., 1991, 113, 15, 5573, https://doi.org/10.1021/ja00015a009 . [all data]

Paulino and Squires, 1991, 2
Paulino, J.A.; Squires, R.R., Carbene Anion Complexes - Unusual Structural and Thermochemical Features of alpha-Halocarbanions in the Gas Phase, J. Am. Chem. Soc., 1991, 113, 5, 1845, https://doi.org/10.1021/ja00005a067 . [all data]


Notes

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