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  1. Abstract

    Hybrid organic–inorganic perovskites (HOIPs) such as methylammonium lead iodide (MAPbI3) are promising candidates for use in photovoltaic cells and other semiconductor applications, but their limited chemical stability poses obstacles to their widespread use.Ab initiomodeling of finite-temperature and pressure thermodynamic equilibria of HOIPs with their decomposition products can reveal stability limits and help develop mitigation strategies. We here use a previously published experimental temperature-pressure equilibrium to benchmark and demonstrate the applicability of the harmonic and quasiharmonic approximations, combined with a simple entropy correction for the configurational freedom of methylammonium cations in solid MAPbI3and for several density functional approximations, to the thermodynamics of MAPbI3decomposition. We find that these approximations, together with the dispersion-corrected hybrid density functional HSE06, yield remarkably good agreement with the experimentally assessed equilibrium betweenT= 326 K andT= 407 K, providing a solid foundation for future broad thermodynamic assessments of HOIP stability.

     
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  2. Free, publicly-accessible full text available October 1, 2024
  3. Free, publicly-accessible full text available August 1, 2024
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  5. Free, publicly-accessible full text available August 16, 2024
  6. Abstract

    This Roadmap article provides a succinct, comprehensive overview of the state of electronic structure methods and software for molecular and materials simulations. Seventeen distinct sections collect insights by 51 leading scientists in the field. Each contribution addresses the status of a particular area, as well as current challenges and anticipated future advances, with a particular eye towards software related aspects and providing key references for further reading. Foundational sections cover density functional theory and its implementation in real-world simulation frameworks, Green's function based many-body perturbation theory, wave-function based and stochastic electronic structure approaches, relativistic effects and semiempirical electronic structure theory approaches. Subsequent sections cover nuclear quantum effects, real-time propagation of the electronic structure, challenges for computational spectroscopy simulations, and exploration of complex potential energy surfaces. The final sections summarize practical aspects, including computational workflows for complex simulation tasks, the impact of current and future high-performance computing architectures, software engineering practices, education and training to maintain and broaden the community, as well as the status of and needs for electronic structure based modeling from the vantage point of industry environments. Overall, the field of electronic structure software and method development continues to unlock immense opportunities for future scientific discovery, based on the growing ability of computations to reveal complex phenomena, processes and properties that are determined by the make-up of matter at the atomic scale, with high precision.

     
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  7. null (Ed.)