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Abstract The excited-state properties of molecular crystals are important for applications in organic electronic devices. TheGWapproximation and Bethe-Salpeter equation (GW+BSE) is the state-of-the-art method for calculating the excited-state properties of crystalline solids with periodic boundary conditions. We present the PAH101 dataset ofGW+BSE calculations for 101 molecular crystals of polycyclic aromatic hydrocarbons (PAHs) with up to  ~500 atoms in the unit cell. To the best of our knowledge, this is the firstGW+BSE dataset for molecular crystals. The data records include theGWquasiparticle band structure, the fundamental band gap, the static dielectric constant, the first singlet exciton energy (optical gap), the first triplet exciton energy, the dielectric function, and optical absorption spectra for light polarized along the three lattice vectors. The dataset can be used to (i) discover materials with desired electronic/optical properties, (ii) identify correlations between DFT andGW+BSE quantities, and (iii) train machine learned models to help in materials discovery efforts. 

Antimony selenide (Sb2Se3) is a promising material for solar energy conversion due to its low toxicity, high stability, and excellent light absorption capabilities. However, Sb2Se3 films produced via physical vapor deposition often exhibit Se-deficient surfaces, which result in a high carrier recombination and poor device performance. The conventional selenization process was used to address selenium loss in Sb2Se3 solar cells with a substrate configuration. However, this traditional selenization method is not suitable for superstrated Sb2Se3 devices with the window layer buried underneath the Sb2Se3 light absorber layer, as it can lead to significant diffusion of the window layer material into Sb2Se3 and damage the device. In this work, we have demonstrated a rapid thermal selenization (RTS) technique that can effectively selenize the Sb2Se3 absorber layer while preventing the S diffusion from the buried CdS window layer into the Sb2Se3 absorber layer. The RTS technique significantly reduces carrier recombination loss and carrier transport resistance and can achieve the highest efficiency of 8.25%. Overall, the RTS method presents a promising approach for enhancing low-dimensional chalcogenide thin films for emerging superstrate chalcogenide solar cell applications. 

The excited-state properties of molecular crystals are important for applications in organic electronic devices. The GW approximation and Bethe-Salpeter equation (GW+BSE) is the state-of-the-art method for calculating the excited-state properties of crystalline solids with periodic boundary conditions. We present the PAH101 dataset of GW +BSE calculations for 101 molecular crystals of polycyclic aromatic hydrocarbons (PAHs) with up to ∼500 atoms in the unit cell. The data records include the GW quasiparticle band structure, the fundamental band gap, the static dielectric constant, the first singlet exciton energy (optical gap), the first triplet exciton energy, the dielectric function, and optical absorption spectra for light polarized along the three lattice vectors. In addition, the dataset includes the density functional theory (DFT) single-molecule and crystal features used in Liu et al. [npj Computational Materials, 8, 70 (2022)]. We envision the dataset being used to (i) identify correlations between DFT and GW +BSE quantities, (ii) discover materials with desired electronic/ optical properties in the dataset itself, and (iii) train machine-learned models to help in materials discovery efforts. We provide examples to illustrate these three use cases. 

The excited-state properties of molecular crystals are important for applications in organic electronic devices. The GW approximation and Bethe-Salpeter equation (GW +BSE) is the state-of-the-art method for calculating the excited-state properties of crystalline solids with periodic boundary conditions. We present the PAH101 dataset of GW +BSE calculations for 101 molecular crystals of polycyclic aromatic hydrocarbons (PAHs) with up to ∼500 atoms in the unit cell. The data records include the GW quasiparticle band structure, the fundamental band gap, the static dielectric constant, the first singlet exciton energy (optical gap), the first triplet exciton energy, the dielectric function, and optical absorption spectra for light polarized along the three lattice vectors. In addition, the dataset includes the density functional theory (DFT) single-molecule and crystal features used in Liu et al. [npj Computational Materials, 8, 70 (2022)]. We envision the dataset being used to (i) identify correlations between DFT and GW +BSE quantities, (ii) discover materials with desired electronic/ optical properties in the dataset itself, and (iii) train machine-learned models to help in materials discovery efforts. We provide examples to illustrate these three use cases. 

The true molecular conformation and the crystal structure of benzo[ e ]dinaphtho[2,3- a ;1′,2′,3′,4′- ghi ]fluoranthene, 7,14-diphenylnaphtho[1,2,3,4- cde ]bisanthene and 7,16-diphenylnaphtho[1,2,3,4- cde ]helianthrene were determined ab initio by 3D electron diffraction. All three molecules are remarkable polycyclic aromatic hydrocarbons. The molecular conformation of two of these compounds could not be determined via classical spectroscopic methods due to the large size of the molecule and the occurrence of multiple and reciprocally connected aromatic rings. The molecular structure of the third molecule was previously considered provisional. These compounds were isolated as by-products in the synthesis of similar products and were at the same time nanocrystalline and available only in very limited amounts. 3D electron diffraction data, taken from submicrometric single crystals, allowed for direct ab initio structure solution and the unbiased determination of the internal molecular conformation. Detailed synthetic routes and spectroscopic analyses are also discussed. Based on many-body perturbation theory simulations, benzo[ e ]dinaphtho[2,3- a ;1′,2′,3′,4′- ghi ]fluoranthene may be a promising candidate for triplet–triplet annihilation and 7,14-diphenylnaphtho[1,2,3,4- cde ]bisanthene may be a promising candidate for intermolecular singlet fission in the solid state. 

Antimony selenide (Sb₂Se₃) emerges as a promising sunlight absorber in thin film photovoltaic applications due to its excellent light absorption properties and carrier transport behavior, attributed to the quasi‐one‐dimensional Sb₄Se₆‐nanoribbon crystal structure. Overcoming the challenge of aligning Sb₂Se₃‐nanoribbons normal to substrates for efficient photogenerated carrier extraction, a solution‐processed nanocrystalline Sb₂(S,Se)₃‐seeds are employed on the CdS buffer layer. These seeds facilitate superstrated Sb₂Se₃thin film solar cell growth through a close‐space sublimation approach. The Sb₂(S,Se)₃‐seeds guided the Sb₂Se₃absorber growth along a [002]‐preferred crystal orientation, ensuring a smoother interface with the CdS window layer. Remarkably, Sb₂(S,Se)₃‐seeds improve carrier transport, reduce series resistance, and increase charge recombination resistance, resulting in an enhanced power conversion efficiency of 7.52%. This cost‐effective solution‐processed seeds planting approach holds promise for advancing chalcogenide‐based thin film solar cells in large‐scale manufacturing.