Fundamental flaw found in widely-used quantum simulation method
Researchers have identified critical problems in a popular computational shortcut used to model materials and molecular behavior—findings that could affect the reliability of predictions in drug discovery, battery design, and semiconductor development. The flaw stems from a mathematical assumption that, while theoretically elegant, produces erratic results in real-world applications.
Originaltitel: Challenges for semilocal density functionals with asymptotically nonvanishing potentials
<p>The Becke-Johnson model potential [A. D. Becke and E. R. Johnson, J. Chem. Phys. 124, 221101 ( 2006)] and the potential of the AK13 functional [R. Armiento and S. Kummel, Phys. Rev. Lett. 111, 036402 ( 2013)] have been shown to mimic features of the exact Kohn-Sham exchange potential, such as step structures that are associated with shell closings and particle-number changes. A key element in the construction of these functionals is that the potential has a limiting value far outside a finite system that is a system-dependent constant rather than zero. We discuss a set of anomalous features in these functionals that are closely connected to the nonvanishing asymptotic potential. The findings constitute a formidable challenge for the future development of semilocal functionals based on the concept of a nonvanishing asymptotic constant.</p>