What is Functionals: Definition and 41 Discussions

Minnesota Functionals (Myz) are a group of highly parameterized approximate exchange-correlation energy functionals in density functional theory (DFT). They are developed by the group of Prof. Donald Truhlar at the University of Minnesota.
These functionals are based on the meta-GGA approximation, i.e. they include terms that depend on the kinetic energy density, and are all based on complicated functional forms parametrized on high-quality benchmark databases.
These functionals can be used for traditional quantum chemistry and solid-state physics calculations. The Myz functionals are widely used and tested in the quantum chemistry community.Independent evaluations of the strengths and limitations of the Minnesota functionals with respect to various chemical properties have, however, cast doubts on the accuracy of Minnesota functionals. Some regard this criticism to be unfair. In this view, because Minnesota functionals are aiming for a balanced description for both main-group and transition-metal chemistry, the studies assessing Minnesota functionals solely based on the performance on main-group databases yield biased information, as the functionals that work well for main-group chemistry may fail for transition metal chemistry.
A study in 2017 highlighted the poor performance of Minnesota functionals on atomic densities. Some others have refuted this criticism claiming that focusing only on atomic densities (including chemically unimportant, highly charged cations) is hardly relevant to real applications of density functional theory in computational chemistry. A recent study has found this to be the case: for Minnesota functionals (which are very popular in computational chemistry for calculating energy-related quantities), the errors in atomic densities and in energetics are indeed decoupled, and the Minnesota functionals perform better for diatomic densities than for the atomic densities. The study concludes that atomic densities do not yield an accurate judgement of the performance of density functionals. Minnesota functionals have also been shown to reproduce chemically relevant Fukui functions better than they do the atomic densities.Minnesota functionals are available in a large number of popular quantum chemistry computer programs.

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  2. B

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  4. J

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  11. J

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  12. T

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  13. D

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  14. D

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  15. B

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  16. Matterwave

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  17. G

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  18. A

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  19. M

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  31. jaketodd

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  32. D

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  33. M

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  34. P

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  35. S

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  36. R

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  37. W

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  38. W

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  39. W

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  40. MathematicalPhysicist

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  41. U

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