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The potential energy surface of ZnnOn clusters (n = 2, 4, 6, 8) has been explored by using a simulated annealing method. For n = 2, 4, and 6, the CCSD(T)/TZP method was used as the reference, and from here it is shown that the M06-2X/TZP method gives the lowest deviations over PBE, PBE0, B3LYP, M06, and MP2 methods. Thus, with the M06-2X method we predict isomers of ZnnOn clusters, which coincide with some isomers reported previously. By using the atoms in molecules analysis, possible contacts between Zn and O atoms were found for all structures studied in this article. The bond paths involved in several clusters suggest that ZnnOn clusters can be obtained from the zincite (ZnO crystal), such an observation was confirmed for clusters with n = 2 − 9,18 and 20. The structure with n = 23 was obtained by the procedure presented here, from crystal information, which could be important to confirm experimental data delivered for n = 18 and 23. [ABSTRACT FROM AUTHOR]

The analysis of scalar and vector fields in quantum chemistry is an essential task for the computational chemistry community, where such quantities must be evaluated rapidly to perform a particular study. For example, the atoms in molecules approach proposed by Bader has become popular; however, this method demands significant computational resources to compute the involved tasks in short times. In this article, we discuss the importance of graphics processing units (GPU) to analyze electron density, and related fields, implementing several scalar, and vector fields within the graphics processing units for atoms and molecules (GPUAM) code developed by a group of the Universidad Autónoma Metropolitana in México City. With this application, the quantum chemistry community can perform demanding computational tasks on a desktop, where CPUs and GPUs are used to their maximum capabilities. The performance of GPUAM is tested in several systems and over different GPUs, where a GPU installed in a workstation converts it to a robust high‐performance computing system. The Graphics Processing Units for Atoms in Molecules (GPUAM) project is benchmarked in several systems and over different GPUs, where a GPU installed in a workstation converts it to a robust high‐performance computing system. Developed at the Universidad Autónoma Metropolitana in México City, GPUAM can evaluate electron density, or related scalar or vector quantum chemistry fields, using CPUs and GPUs over desktops, or high‐performance computing hardware. [ABSTRACT FROM AUTHOR]