Informatics Institute faculty member Adem Tekin, research assistant Mehmet Çankaya, former research assistants Samet Demir and Gözde İniş Demir coauthored paper titled 'Stable and metastable crystal structures and ammonia dynamics in strontium chloride ammines' has been published in 'Physical Chemistry Chemical Physics' dergisinde on 18th September 2023.


DOI: https://doi.org/10.1039/D3CP04114J


Abstract: Metal halide ammines are promising ammonia storage materials due to their high ammonia densities and suitable decomposition properties. Here, we studied the polymorphism of ammines with a general formula of Sr(NH3)nCl2 (n = 1, 2, 4, 6, and 8) by combining the Fast and Flexible CrystAl Structure Predictor (FFCASP) with density functional theory (DFT) calculations. Furthermore, the lattice stability and the minimum energy paths for bulk and surface diffusion of NH3 were investigated by performing phonon and nudged elastic band (NEB) calculations. In addition to the successful reproduction of the reported experimental crystal structures of octammine (Pnma (IT number 62)), diammine (Aem2 (IT number 39)) and monoammine (Cmcm (IT number 63)), several isoenergetic polymorphs for each phase were also found. Not only the experimentally determined octammine and monoammine structures, but also the proposed structures for the hexammine and tetrammine phases were found to be metastable. While phonon calculations show instability for the experimental diammine structure, some of the proposed structures for the diammine phase showed thermodynamical stability. Moreover, NEB paths examining the bulk and surface diffusion of NH3 are in accordance with the experimental desorption enthalpies.
 

İTÜ Informatics Institute

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ITU Informatics Institute provides graduate-level education and research in applied informatics, computer sciences, computational science and engineering, communication systems under the following programs.

Faculty members and students conduct research supported by national and international organızatıons in the fields of electromagnetic fields, communication systems/regulations, computational materials design, computational chemistry/biology, cryptography, signal/data processing/visualization, big data management, climate and ocean sciences, 

  • List of Most Influential Scientists; Associate Professor. B. Uğur Töreyin (article by Dr. John PA Ioannidis, K. W. Boyack and J. Baas published in the journal PLOS Biology)
  • Beltus Nkwawir Wiysobunri, the best project award in the Science category, in the 2020 International Students Project Competition
  • Argenit company, of which Dr. Abdulkerim Çapar is among the founding partners, received the "National-International Supports" First Prize of ITU ARI Teknokent.
  • TÜBİTAK 2242 University Students Project Competition in Priority Areas: Istanbul region first place - Ahmet Burak Özyurt
  • Best Presentation Award at ICAT'18 Conference: Sena Efsun Cebeci, 2018
  • Tubitak Incentive Award; 2016 Assoc. Prof. Adem Tekin
  • “Technical Paper” and “Willis H. Carrier” Award by the American Heating, Cooling and Air Conditioning Association; 2016 Assist. Prof. Dr. H. Salih Erden
  • Science Heroes Association Young Scientist of the Year Award; 2016 Assoc. B. Uğur Töreyin Best Poster Award at PRACEdays 2016 conference; Samet Demir
  • ITU Most Successful Thesis Award; 2016 Hatice Gokcan

There is also a High Performance Computing Laboratory established with the support of the State Planning Organization within the Institute.