rmgpy.thermo.ThermoData¶

class
rmgpy.thermo.
ThermoData
(Tdata=None, Cpdata=None, H298=None, S298=None, Cp0=None, CpInf=None, Tmin=None, Tmax=None, E0=None, label='', comment='')¶ A heat capacity model based on a set of discrete heat capacity data points. The attributes are:
Attribute Description Tdata An array of temperatures at which the heat capacity is known Cpdata An array of heat capacities at the given temperatures H298 The standard enthalpy of formation at 298 K S298 The standard entropy at 298 K Tmin The minimum temperature at which the model is valid, or zero if unknown or undefined Tmax The maximum temperature at which the model is valid, or zero if unknown or undefined E0 The energy at zero Kelvin (including zero point energy) comment Information about the model (e.g. its source) 
Cp0
¶ The heat capacity at zero temperature.

CpInf
¶ The heat capacity at infinite temperature.

Cpdata
¶ An array of heat capacities at the given temperatures.

E0
¶ The ground state energy (J/mol) at zero Kelvin, including zero point energy, or
None
if not yet specified.

H298
¶ The standard enthalpy of formation at 298 K.

S298
¶ The standard entropy of formation at 298 K.

Tdata
¶ An array of temperatures at which the heat capacity is known.

Tmax
¶ The maximum temperature at which the model is valid, or
None
if not defined.

Tmin
¶ The minimum temperature at which the model is valid, or
None
if not defined.

comment
¶ comment – str

discrepancy
(self, HeatCapacityModel other) → double¶ Return some measure of how dissimilar self is from other.
The measure is arbitrary, but hopefully useful for sorting purposes. Discrepancy of 0 means they are identical

getEnthalpy
(self, double T) → double¶ Return the enthalpy in J/mol at the specified temperature T in K.

getEntropy
(self, double T) → double¶ Return the entropy in J/mol*K at the specified temperature T in K.

getFreeEnergy
(self, double T) → double¶ Return the Gibbs free energy in J/mol at the specified temperature T in K.

getHeatCapacity
(self, double T) → double¶ Return the constantpressure heat capacity in J/mol*K at the specified temperature T in K.

isIdenticalTo
(self, HeatCapacityModel other) → bool¶ Returns
True
if self and other report very similar thermo values for heat capacity, enthalpy, entropy, and free energy over a wide range of temperatures, orFalse
otherwise.

isSimilarTo
(self, HeatCapacityModel other) → bool¶ Returns
True
if self and other report similar thermo values for heat capacity, enthalpy, entropy, and free energy over a wide range of temperatures, orFalse
otherwise.

isTemperatureValid
(self, double T) → bool¶ Return
True
if the temperature T in K is within the valid temperature range of the thermodynamic data, orFalse
if not. If the minimum and maximum temperature are not defined,True
is returned.

label
¶ label – str

toNASA
(self, double Tmin, double Tmax, double Tint, bool fixedTint=False, bool weighting=True, int continuity=3) → NASA¶ Convert the object to a
NASA
object. You must specify the minimum and maximum temperatures of the fit Tmin and Tmax in K, as well as the intermediate temperature Tint in K to use as the bridge between the two fitted polynomials. The remaining parameters can be used to modify the fitting algorithm used:fixedTint 
False
to allow Tint to vary in order to improve the fit, orTrue
to keep it fixedweighting 
True
to weight the fit by \(T^{1}\) to emphasize good fit at lower temperatures, orFalse
to not use weightingcontinuity  The number of continuity constraints to enforce at Tint:
 0: no constraints on continuity of \(C_\mathrm{p}(T)\) at Tint
 1: constrain \(C_\mathrm{p}(T)\) to be continous at Tint
 2: constrain \(C_\mathrm{p}(T)\) and \(\frac{d C_\mathrm{p}}{dT}\) to be continuous at Tint
 3: constrain \(C_\mathrm{p}(T)\), \(\frac{d C_\mathrm{p}}{dT}\), and \(\frac{d^2 C_\mathrm{p}}{dT^2}\) to be continuous at Tint
 4: constrain \(C_\mathrm{p}(T)\), \(\frac{d C_\mathrm{p}}{dT}\), \(\frac{d^2 C_\mathrm{p}}{dT^2}\), and \(\frac{d^3 C_\mathrm{p}}{dT^3}\) to be continuous at Tint
 5: constrain \(C_\mathrm{p}(T)\), \(\frac{d C_\mathrm{p}}{dT}\), \(\frac{d^2 C_\mathrm{p}}{dT^2}\), \(\frac{d^3 C_\mathrm{p}}{dT^3}\), and \(\frac{d^4 C_\mathrm{p}}{dT^4}\) to be continuous at Tint
Note that values of continuity of 5 or higher effectively constrain all the coefficients to be equal and should be equivalent to fitting only one polynomial (rather than two).
Returns the fitted
NASA
object containing the two fittedNASAPolynomial
objects.

toWilhoit
(self, B=None) → Wilhoit¶ Convert the Benson model to a Wilhoit model. For the conversion to succeed, you must have set the Cp0 and CpInf attributes of the Benson model.
B: the characteristic temperature in Kelvin.
