Alessandro Stroppa

Hybrid functionals applied to extended systems

We present an overview of the description of structural, thermochemical, and electronic properties of extended systems using several well known hybrid Hartree-Fock/density-functional-theory functionals (PBE0, HSE03, and B3LYP). In addition we address a few aspects of the evaluation of the Hartree-Fock exchange interactions in reciprocal space, relevant to all methods that employ a plane wave basis set and periodic boundary conditions.

Accurate surface and adsorption energies from many-body perturbation theory

Kohn-Sham density functional theory is the workhorse computational method in materials and surface science. Unfortunately, most semilocal density functionals predict surfaces to be more stable than they are experimentally. Naively, we would expect that consequently adsorption energies on surfaces are too small as well, but the contrary is often found: chemisorption energies are usually overestimated. Modifying the functional improves either the adsorption energy or the surface energy but always worsens the other aspect. This suggests that semilocal density functionals possess a fundamental flaw that is difficult to cure, and alternative methods are urgently needed. Here we show that a computationally fairly efficient many-electron approach, the random phase approximation to the correlation energy, resolves this dilemma and yields at the same time excellent lattice constants, surface energies and adsorption energies for carbon monoxide and benzene on transition-metal surfaces.

Hybrid Improper Ferroelectricity in a Multiferroic and Magnetoelectric Metal-Organic Framework

There is great interest in hybrid organic-inorganic materials such as metal-organic frameworks (MOFs). The compounds [C(NH

Tuning the ferroelectric polarization in a multiferroic metal-organic framework.

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The shortcomings of semi-local and hybrid functionals: what we can learn from surface science studies

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Cross coupling between electric and magnetic orders in a multiferroic metal-organic framework

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CO adsorption on metal surfaces: A hybrid functional study with plane-wave basis set

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Magnetism in C- or N-doped MgO and ZnO: A Density-Functional Study of Impurity Pairs

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Hybrid functional study of proper and improper multiferroics

, where M=Cu

Unraveling the Jahn-Teller effect in Mn-doped GaN using the Heyd-Scuseria-Ernzerhof hybrid functional

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