Average Pressure¶
Scalar Thermodynamic
We define the Average Pressure p_{avg} of a Material as a Scalar and Physical property obtained from the following conventional formula.
p_{avg}=-\frac{1}{3} \mathrm{Tr} \hspace{1pt} {\boldsymbol{\sigma}}
where {\boldsymbol{\sigma}} is the internal stress tensor of the solid, and \mathrm{Tr} indicates the Trace operator in linear algebra 1.
Example¶
The average pressure can be computed as part of any Workflow involving at least one basic "self-consistent field" (scf) total energy calculation in DFT.
It is then presented to the user, as part of the output of a Job, with the following appearance under the interface of the Results Tab of Job Viewer. Its final value is expressed in units of kilobars (kbar).
Pressure
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Schema¶
The JSON schema and an example representation for this property can be found here.