Neural-network-backed evolutionary search for SrTiO(110) surface reconstructions.

The determination of atomic structures in surface reconstructions has typically relied on structural models derived from intuition and domain knowledge. Evolutionary algorithms have emerged as powerful tools for such structure searches. However, when density functional theory is used to evaluate the energy the computational cost of a thorough exploration of the potential energy landscape is prohibitive.

Phosphate-Templated Encapsulation of a {Co O } Cubane in Germanotungstates as Carbon-Free Homogeneous Water Oxidation Photocatalysts.

The ever-growing interest in sustainable energy sources leads to a search for an efficient, stable, and inexpensive homogeneous water oxidation catalyst (WOC). Herein, the PO templated synthesis of three abundant-metal-based germanotungstate (GT) clusters Na [Ge PCo (H O) W O ] ⋅ 38H O (Co ), Na K [Ge PCo (OH) (H O) W O ] ⋅ 45H O (Co ), Na K [Ge P Co (OH) (H O) W O ] ⋅ 61H O (Co ) with non-, quasi-, or full cubane motifs structurally strongly reminiscent of the naturally occurring {Mn Ca} oxygen evolving complex (OEC) in photosystem II was achieved. Under the conditions tested, all three GT-scaffolds were active molecular WOCs, with Co and Co outperforming the well-known Na [Co (H O) (PW O ) ] {Co P W } by a factor of 2 as shown by a direct comparison of their turnover numbers (TONs).

A comparative first-principles investigation on the defect chemistry of TiO anatase.

Understanding native point defects is fundamental in order to comprehend the properties of TiO anatase in technological applications. The previous first-principles reports of defect-relevant quantities, such as formation energies and charge transition levels, are, however, scattered over a wide range. We perform a comparative study employing different approaches based on semilocal with Hubbard correction (DFT+U) and screened hybrid functionals in order to investigate the dependence defect properties on the employed computational method.

First principles study of confinement effects for oxygen vacancies in BaZrO₃ (001) ultra-thin films.

In this contribution, we study possible confinement effects on the atomic and electronic structure, and phonon properties of neutral (V(O)(x) and fully charged (V(O)oxygen vacancies in BaZrO3 (001) ultra-thin films. First principles phonon calculations were performed as a function of film thickness (from 3 to 7 atomic planes) with two complementary DFT methods. The calculations reveal that for both types of vacancies the confinement effect is very short-range; for films containing 5 planes or more, the oxygen vacancy properties are predicted to be similar to those observed in the bulk material.

Thermodynamic properties of neutral and charged oxygen vacancies in BaZrO3 based on first principles phonon calculations.

The structural, electronic and thermodynamic properties of neutral and positively doubly charged oxygen vacancies in BaZrO3 are addressed by first principles phonon calculations. The calculations are performed using two complementary first principles approaches and functionals; the linear combination of atomic orbitals (LCAO) within the hybrid Hartree-Fock and density functional theory formalism (HF-DFT), and the projector augmented plane wave approach (PAW) within DFT. Phonons are shown to contribute significantly to the formation energy of the charged oxygen vacancy at high temperatures (∼1 eV at 1000 K), due to both its large distortion of the local structure, and its large negative formation volume.