PARATEC (PARAllel Total Energy Code) is a package that performs
ab initio
''Ab initio'' ( ) is a Latin term meaning "from the beginning" and is derived from the Latin ''ab'' ("from") + ''initio'', ablative singular of ''initium'' ("beginning").
Etymology
Circa 1600, from Latin, literally "from the beginning", from ab ...
quantum mechanical
Quantum mechanics is a fundamental theory in physics that provides a description of the physical properties of nature at the scale of atoms and subatomic particles. It is the foundation of all quantum physics including quantum chemistry, qua ...
total energy
In physics, energy (from Ancient Greek: ἐνέργεια, ''enérgeia'', “activity”) is the quantitative property that is transferred to a body or to a physical system, recognizable in the performance of work and in the form of heat ...
calculations using
pseudopotential
In physics, a pseudopotential or effective potential is used as an approximation for the simplified description of complex systems. Applications include atomic physics and neutron scattering. The pseudopotential approximation was first introduced ...
s and a
plane wave
In physics, a plane wave is a special case of wave or field: a physical quantity whose value, at any moment, is constant through any plane that is perpendicular to a fixed direction in space.
For any position \vec x in space and any time t, th ...
basis set. PARATEC is designed primarily for a
massively parallel
Massively parallel is the term for using a large number of computer processors (or separate computers) to simultaneously perform a set of coordinated computations in parallel. GPUs are massively parallel architecture with tens of thousands of t ...
computing platform
A computing platform or digital platform is an environment in which a piece of software is executed. It may be the hardware or the operating system (OS), even a web browser and associated application programming interfaces, or other underlying s ...
, and can run on serial machines. Calculations of
XANES
X-ray absorption near edge structure (XANES), also known as near edge X-ray absorption fine structure (NEXAFS), is a type of absorption spectroscopy that indicates the features in the X-ray absorption spectra ( XAS) of condensed matter due to the ...
within such a full-potential approach has been implemented within PARATEC.
The total energy minimization of the
electron
The electron ( or ) is a subatomic particle with a negative one elementary electric charge. Electrons belong to the first generation of the lepton particle family,
and are generally thought to be elementary particles because they have no kn ...
s can be done by two methods: (i) the more traditional
self-consistent field
In classical deductive logic, a consistent theory is one that does not lead to a logical contradiction. The lack of contradiction can be defined in either semantic or syntactic terms. The semantic definition states that a theory is consistent ...
(SCF) method and (ii) direct minimization (currently only implemented for systems with a gap) of the total energy.
References
*
* {{cite journal , last1=Taillefumier , first1=Mathieu , last2=Cabaret , first2=Delphine , last3=Flank , first3=Anne-Marie , last4=Mauri , first4=Francesco , title=X-ray absorption near-edge structure calculations with the pseudopotentials: Application to the K edge in diamond and α-quartz , journal=Physical Review B , publisher=American Physical Society (APS) , volume=66 , issue=19 , date=2002-11-18 , issn=0163-1829 , doi=10.1103/physrevb.66.195107 , page=195107, arxiv=cond-mat/0207733 , s2cid=53308221
External links
PARATEC home page
Physics software