Experimental and theoretical study of the dissociation enthalpy of the N-O bond on 2-hydroxypyridine N-oxide: theoretical analysis of the energetics of the N-O bond for hydroxypyrydine N-oxide isomers
Ribeiro da Silva, M. D. M. C.[Maria D. M. C.], Matos, M. A. R.[M. Agostinha R.], Miranda, M. S.[Margarida S.], Morais, V. M. F.[Victor M. F.], Acree, Jr., W. E.[William E.]
The standard (po=0.1 MPa) molar enthalpy of formation of crystalline 2-hydroxypyridine N-oxide was measured, at T=298.15 K, by static bomb calorimetry and the standard molar enthalpy of sublimation, at T=298.15 K, was obtained using Calvet microcalorimetry. These values were used to derive the standard molar enthalpy of formation of 2-hydroxypyridine N-oxide in gaseous phase, and to evaluate the dissociation enthalpy of the N-O bond. Additionally, high-level density functional theory calculations using the B3LYP hybrid exchange-correlation energy functional have been performed for the three isomers of hydroxypyridine N-oxide in order to confirm the experimental trend for the dissociation enthalpy of the (N-O) bond.
Compounds
#
Formula
Name
1
CO2
carbon dioxide
2
N2
nitrogen
3
H2O
water
4
O2
oxygen
5
C5H5NO2
2-hydroxypyridine-N-oxide
Datasets
The table above is generated from the ThermoML associated json file (link above).
POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied;
the numbers refer to the table of compounds on the left.
Type
Compound-#
Property
Variable
Constraint
Phase
Method
#Points
POMD
5
Molar enthalpy, kJ/mol ; Gas
Temperature, K; Gas
Pressure, kPa; Gas
Gas
OTHER
1
RXND
5
1
2
3
4
Specific internal energy of reaction at constant volume, J/g