Wiley Interdisciplinary Reviews: Computational Molecular Science

Seritan, Stefan; Bannwarth, Christoph; Fales, Bryan S.; Hohenstein, Edward G.; Isborn, Christine M.; Kokkila‐Schumacher, Sara I. L.; Li, Xin; Liu, Fang; Luehr, Nathan; Snyder, James W.; Song, Chenchen; Titov, Alexey V.; Ufimtsev, Ivan S.; Wang, Lee‐Ping; Martínez, Todd J.

doi: 10.1002/wcms.1523pmid: N/A

You, Peiwei; Chen, Daqiang; Lian, Chao; Zhang, Cui; Meng, Sheng

doi: 10.1002/wcms.1492pmid: N/A

The past decades have witnessed the success of ground‐state density functional theory capturing static electronic properties of various materials. However, for time dependent processes especially those involving excited states, real‐time time‐dependent density functional theory (rt‐TDDFT) and advanced nonadiabatic algorithms are essential, especially for practical simulations of molecules and materials under the occurrence of ultrafast laser field. Here we summarize the recent progresses in developing rt‐TDDFT approaches within numerical atomic orbitals and planewave formalisms, as well as the efforts combining rt‐TDDFT and ring polymer molecular dynamics to take into account nuclear quantum effects in quantum electronic‐nuclear dynamic simulations. Typical applications of first‐principles dynamics of excited electronic states including high harmonic generation, charge density wave, photocatalytic water splitting, as well as quantum nuclear motions in ozone and graphene, are presented to demonstrate the features and advantages of these methods. The progresses in method developments and practical applications provide unprecedented insights into nonadiabatic dynamics of excited states in the Ehrenfest scheme and beyond, towards a comprehensive understanding of excited electronic structure, electron–phonon interactions, photoinduced charge transfer and chemical reactions, as well as quantum nuclear motions in excited states.

Bannwarth, Christoph; Caldeweyher, Eike; Ehlert, Sebastian; Hansen, Andreas; Pracht, Philipp; Seibert, Jakob; Spicher, Sebastian; Grimme, Stefan

doi: 10.1002/wcms.1493pmid: N/A

This review covers a family of atomistic, mostly quantum chemistry (QC) based semiempirical methods for the fast and reasonably accurate description of large molecules in gas and condensed phase. The theory is derived from a density functional (DFT) perturbation expansion of the electron density in fluctuation terms to various orders similar to the original density functional tight binding model. The term “eXtended” in their name (xTB) emphasizes the parameter availability for almost the entire periodic table of elements (Z ≤ 86) and improvements of the underlying theory regarding, for example, the atomic orbital basis set, the level of multipole approximation and the treatment of the important electrostatic and dispersion interactions. A common feature of most members is their consistent parameterization on accurate gas phase theoretical reference data for geometries, vibrational frequencies and noncovalent interactions, which are the primary properties of interest in typical applications to systems composed of up to a few thousand atoms. Further specialized versions were developed for the description of electronic spectra and corresponding response properties. Besides a provided common theoretical background with some important implementation details in the efficient and free xtb program, various benchmarks for structural and thermochemical properties including (transition‐)metal systems are discussed. The review is completed by recent extensions of the model to the force‐field (FF) level as well as its application to solids under periodic boundary conditions. The general applicability together with the excellent cost‐accuracy ratio and the high robustness make the xTB family of methods very attractive for various fields of computer‐aided chemical research.

Laplaza, Rubén; Peccati, Francesca; A. Boto, Roberto; Quan, Chaoyu; Carbone, Alessandra; Piquemal, Jean‐Philip; Maday, Yvon; Contreras‐García, Julia

doi: 10.1002/wcms.1497pmid: N/A

Noncovalent interactions are of utmost importance. However, their accurate treatment is still difficult. This is partially induced by the coexistence of many types of interactions and physical phenomena, which hampers generality in simple treatments. The NCI index has been successfully used for nearly over 10 years in order to identify, analyze, and understand noncovalent interactions in a wide variety of systems, ranging from proteins to molecular crystals. In this work, the development and implications of the method will be reviewed, and modern implementations will be presented. Afterward, some sophisticated examples will be given that showcase the current advances toward the fast, robust, and intuitive identification of noncovalent interactions in real space.

Fornari, Rocco Peter; Silva, Piotr

doi: 10.1002/wcms.1495pmid: N/A

Organic redox‐active battery materials are an emerging alternative to their inorganic counterparts currently used in the commercialized battery technologies. The main advantages of organic batteries are the potential for low‐cost manufacturing, tunability of electrochemical properties through molecular engineering, and their environmental sustainability. The search for organic electroactive materials that could be used for energy storage in mobile and stationary applications is an active area of research. Computer simulations are used extensively to improve the understanding of the fundamental processes in the existing materials and to accelerate the discovery of new materials with improved performance. We will focus on two main types of redox‐active organic battery materials, that is, solid‐state organic electrode materials and organic electrolytes for redox flow batteries. Because organic materials are made of molecular building blocks, the molecular modeling methodology is usually the most appropriate to investigate their properties at the electronic and atomistic scales. After introducing the fundamentals of computational organic electrochemistry, we will survey its most recent applications in organic battery research and outline some of the remaining challenges for the development and applications of atomic‐scale modeling techniques in the organic battery context.

doi: 10.1002/wcms.1484pmid: N/A

Smith, Daniel G. A.; Altarawy, Doaa; Burns, Lori A.; Welborn, Matthew; Naden, Levi N.; Ward, Logan; Ellis, Sam; Pritchard, Benjamin P.; Crawford, T. Daniel

doi: 10.1002/wcms.1491pmid: N/A

The Molecular Sciences Software Institute's (MolSSI) Quantum Chemistry Archive (QCArchive) project is an umbrella name that covers both a central server hosted by MolSSI for community data and the Python‐based software infrastructure that powers automated computation and storage of quantum chemistry (QC) results. The MolSSI‐hosted central server provides the computational molecular sciences community a location to freely access tens of millions of QC computations for machine learning, methodology assessment, force‐field fitting, and more through a Python interface. Facile, user‐friendly mining of the centrally archived quantum chemical data also can be achieved through web applications found at https://qcarchive.molssi.org. The software infrastructure can be used as a standalone platform to compute, structure, and distribute hundreds of millions of QC computations for individuals or groups of researchers at any scale. The QCArchive Infrastructure is open‐source (BSD‐3C), code repositories can be found at https://github.com/MolSSI, and releases can be downloaded via PyPI and Conda.

Shang, Jing; Tang, Xiao; Kou, Liangzhi

doi: 10.1002/wcms.1496pmid: N/A

The recent emerged two‐dimensional (2D) ferroelectrics have attracted tremendous research interests due to their promising application in nonvolatile electronics devices. The reversible electric polarization of ferroelectrics from the off‐centered positive and negative surfaces can effectively lift the band states near Fermi level and modulate the charge distribution, which therefore play important roles for the controllable electronic/magnetic properties and chemical reactions. Here, based on the latest revealed 2D ferroelectrics, we reviewed the research progress of ferroelectric controlled physical properties and chemical reactions, including the effects of reversible polarization on magnetic and electronic behaviors, polarization dependent photocatalytic water splitting and gas adsorptions. The associated applications in electronics, sensors and energy conversion are also discussed. At last, the possible research directions of 2D ferroelectrics have also been proposed. The review is expected to inspire the research interests of 2D ferroelectrics in the practical applications.