QuantumChemistry
Thermodynamics
compute the thermodynamic properties of a molecule
Calling Sequence
Parameters
Description
Examples
Thermodynamics(molecule, method, options)
molecule
-
list of lists; each list has 4 elements, the string of an atom's symbol and atom's x, y, and z coordinates
method
name/procedure where name is one of 'HartreeFock', 'DensityFunctional', 'RDMFunctional','ActiveSpaceCI', 'ActiveSpaceSCF', 'CoupledCluster', 'FullCI','MP2', 'Variational2RDM', 'Parametric2RDM', 'ContractedSchrodinger'
options
(optional) equation(s) of the form option = value where option is one of temperature, symmetry_number, or any valid option of the chosen method
Thermodynamics computes the thermodynamic properties of a molecule such as energy, enthalpy, entropy, free energy, heat capacity, electronic energy, zero-point energy (ZPE) and rotational temperatures (theta[A], theta[B], theta[C]).
The optional temperature keyword can be used to set the temperature in K. The default is 298.15 K.
The optional symmetry_number keyword can be used to set the symmetry number of the molecule. The default is 1.
Outputs
The table of following contents:
energy
float -- energy in J/mol
enthalpy
float -- enthalpy in J/mol
entropy
float -- entropy in J/(mol K)
free_energy
float -- free energy of the system in J/mol
heat_capacity
float -- heat capacity of the system in J/(mol K)
electronic_energy
float -- electronic energy in J/mol
zpe
float -- zero-point energy in J/mol
θA
float -- rotational temperature (in K) for principle axis A
θB
float -- rotational temperature (in K) for principle axis B
θC
float -- rotational temperature (in K) for principle axis C
with⁡QuantumChemistry:
Define the geometry of the molecule hydrogen fluoride
molecule ≔ H, 0, 0, −0.55, F, 0, 0, +0.55 ;
Optimize the geometry of the molecule
molecule≔H,0,0,−0.55000000,F,0,0,0.55000000
molecule2,output ≔ GeometryOptimizationmolecule,'HartreeFock':
molecule2;
H,0,0,−0.55000000,F,−1.20349177⁢10−11,6.25718917⁢10−11,0.40546311
Using the command Thermodynamics, we can compute the molecule's thermodynamic properties
thermo ≔ Thermodynamicsmolecule2, 'HartreeFock';
thermo≔table⁡free_energy=−2.58849971⁢108⁢Jmol,entropy=365.61292814⁢Jmol⁢K,electronic_energy=−2.58802975⁢108⁢Jmol,zpe=26667.73973739⁢Jmol,heat_capacity=20.78615124⁢Jmol⁢K,θB=27.75734190⁢K,enthalpy=−2.58740963⁢108⁢Jmol,θC=27.75734190⁢K,energy=−2.58743442⁢108⁢Jmol
See Also
HartreeFock DensityFunctional RDMFunctional MP2 CoupledCluster FullCI ActiveSpaceCI ActiveSpaceSCF Variational2RDM Parametric2RDM ContractedSchrodinger
Download Help Document