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07:36
Experimental Procedure for Warm Spinning of Cast Aluminum Components
Published on: February 1, 2017
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Theoretical Study of the Spin Competition in Small-Sized Al Clusters
Omar López-Estrada1, Emilio Orgaz1
1Departamento de Física y Química Teórica, Facultad de Química, Universidad Nacional Autónoma de México , Cd. Universitaria, CP 04510 México, D.F., México.
The Journal of Physical Chemistry. A
|November 20, 2015
Summary
Aluminum clusters Al6 and Al8 exhibit stable singlet spin states at 0 K. At higher temperatures, spin-orbit coupling allows dynamic interchange between singlet and triplet states.
Area of Science:
- Quantum mechanics
- Materials science
- Computational chemistry
Background:
- Stern-Gerlach experiments suggest magnetic moments in aluminum clusters.
- The ground spin state of Al6 and Al8 clusters remains ambiguous.
Purpose of the Study:
- To determine the ground state electronic structure of Al6 and Al8 clusters.
- To investigate the stability of different spin states and their interconversion.
Main Methods:
- Extensive electronic structure computations.
- Inclusion of electron correlation at MP2, MP4, and CCSD(T) levels.
- Density Functional Theory (DFT) with various functionals.
- DFT-based Born-Oppenheimer molecular dynamics.
Main Results:
- Singlet spin states are the more stable configuration at 0 K.
- Electronic structures of singlet and triplet states are nearly degenerate.
- Geometries are similar, facilitating intersystem crossing.
Conclusions:
- Al6 and Al8 clusters favor singlet ground states at absolute zero.
- Spin-orbit coupling enables dynamical interchange between spin states at finite temperatures.
- This dynamic behavior explains experimental observations in Stern-Gerlach experiments.
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