The combination of modern scientific computing with electronic structure theory can lead to an unprecedented amount of data amenable to intelligent data analysis for the identification of meaningful, novel and predictive structure-property relationships. Such relationships enable highthroughput screening for relevant properties in an exponentially growing pool of virtual compounds that are synthetically accessible. Here, we present a machine learning model, trained on a database of ab initio calculation results for thousands of organic molecules, that simultaneously predicts multiple electronic 7

The results of the sixth blind test of organic crystal structure prediction methods are presented and discussed, highlighting progress for salts, hydrates and bulky flexible molecules, as well as on-going challenges.

For a class of 2D hybrid organic-inorganic perovskite semiconductors based on π-conjugated organic cations, we predict quantitatively how varying the organic and inorganic component allows control over the nature, energy and localization of carrier states in a quantum-well-like fashion. Our first-principles predictions, based on large-scale hybrid density-functional theory with spin-orbit coupling, show that the interface between the organic and inorganic parts within a single hybrid can be modulated systematically, enabling us to select between different type-I and type-II energy level alignments. Energy levels, recombination properties and transport behavior of electrons and holes thus become tunable by choosing specific organic functionalizations and juxtaposing them with suitable inorganic components.Hybrid organic-inorganic perovskites (HOIPs), [1, 2] particularly three-dimensional (3D) HOIPs, are currently experiencing a strong revival in interest as economically processable, optically active semiconductor materials with excellent transport characteristics. Their success is showcased most prominently by record performance gains in proof-of-concept photovoltaic [3][4][5][6][7][8][9][10][11][12] and light-emitting devices. [13][14][15][16][17][18][19][20] The electronic function of 3D HOIPs can be tuned to a limited extent by manipulating the inorganic component (from which the frontier orbitals are derived), but the organic cations are confined by the 3D structure and are thus necessarily small (e.g., methylammonium [3][4][5][6][7][8][13][14][15][16][17][18] and formamidinium [9-11, 19, 21, 22]), with electronic levels that do not contribute directly to the electronic functionality. [23][24][25][26][27][28] However, the accessible chemical space of HOIPs extends well beyond the 3D systems. [1] In particular, the layered, socalled two-dimensional (2D) perovskites do not place a strict length constraint on the organic cation. In these materials, a much broader range of functional organic molecules can be incorporated within the inorganic scaffolds, including complex functional molecules such as oligo-acene or -thiophene derivatives. [1,[29][30][31][32][33][34][35][36][37] Fig. 1a shows the atomic structure of a paradigmatic example of such a 2D HOIP with active organic functionality, bis(aminoethyl)-quaterthiophene lead bromide AE4TPbBr 4 .[34] Similar juxtapositions of targeted organic and inorganic components give rise to a vast, yet systematically accessible space of possible semiconductor materials, [1, 2,[38][39][40] including those in which the molecular carrier levels contribute directly to the low-lying excitations and carrier levels. [1, 30-32, 34, 38, 39, 41] This large space of conceivable organic-inorganic combinations thus offers the unique opportunity to tailor (ideally with computational guidance) materials with particularly desirable semiconductor properties, by intentionally controlling the spatial location and character of the electronic carriers and optical excitations throughout the m...

A recently proposed double-hybrid functional called XYG3 and a semilocal GGA functional (B97-D) with a semiempirical correction for van der Waals interactions have been applied to study the potential energy curves along the dissociation coordinates of weakly bound pairs of molecules governed by London dispersion and induced dipole forces. Molecules treated in this work were the parallel sandwich, T-shaped, and parallel-displaced benzene dimer, (C6H6)2; hydrogen sulfide and benzene, H2S·C6H6; methane and benzene, CH4·C6H6; the methane dimer, (CH4)2; and the pyridine dimer, (C5H5N)2. We compared the potential energy curves of these functionals with previously published benchmarks at the coupled cluster singles, doubles, and perturbative triplets [CCSD(T)] complete-basis-set limit. Both functionals, XYG3 and B97-D, exhibited very good performance, reproducing accurate energies for equilibrium distances and a smooth behavior along the dissociation coordinate. Overall, we found an agreement within a few tenths of one kcal mol(-1) with the CCSD(T) results across the potential energy curves.