466 research outputs found
Supplementary data for the article: Malenov, D. P.; Zarić, S. D. Strong Stacking Interactions of Metal-Chelate Rings Are Caused by Substantial Electrostatic Component. Dalton Transactions 2019, 48 (19), 6328–6332. https://doi.org/10.1039/c9dt00182d
Supplementary material for: [https://pubs.rsc.org/en/content/articlelanding/2019/DT/C9DT00182D#!divAbstract]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/3133]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3134
Supplementary data for the article: Malenov, D. P.; Zarić, S. D. Stacking Interactions of Aromatic Ligands in Transition Metal Complexes. Coordination Chemistry Reviews 2020, 419, 213338. https://doi.org/10.1016/j.ccr.2020.213338
Supplementary material for: [https://doi.org/10.1016/j.ccr.2020.213338]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/4030
Supplementary data for article: Blagojević, J. P.; Zarić, S. D. Stacking Interactions of Hydrogen-Bridged Rings-Stronger than the Stacking of Benzene Molecules. Chemical Communications 2015, 51 (65), 12989–12991. https://doi.org/10.1039/c5cc04139b
Supplementary material for: [https://doi.org/10.1039/c5cc04139b]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/1747]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3424
Stacking interactions between chelate and phenyl rings in square-planar complexes of Cu, Ni, Pt and Pd
Previous analysis of geometrical parameters in the crystal structure of square-planar complexes, with and without chelate rings, of all transition metals from Cambridge Structural Database shows that there are stacking interactions between the phenyl ring and the chelate ring with delocalized -bonds. To investigate whether the type of metal atom influence this interaction we compare stacking parameters for the complexes with and without chelate rings in the complexes containing Cu(II), Ni(II), Pd(II) and Pt(II) metals. While the overall picture is similar for all four cases, complexes of Pd and Pt without chelate ring show tendency to form shorter contacts towards aromatic carbon. It was found that this behaviour is associated with the presence of cyano or isocyano derivatives as ligands.Physical chemistry 2006 : 8th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 26-29 September 200
Стекинг интеракције прстенова формираних водоничним везивањем потпомогнутим резонанцијом
Resonance-assisted hydrogen-bridged rings are often found in crystal structures in
parallel alignment; 44% of all crystal structuresfound in Cambridge structural database,
that contain this ring type, form parallel contacts. Distances betw een ring planes are
typical for stacking (3.0-4.0 Å) and rings are in anti orientation.
Quantum chemical calculations of th e stacking interaction energies are
performed using different methods that are in good agreement with CCSD(T)/CBS
methods, on model systems composed on dimers of molecules whose derivatives are the
most common in crystal structures. The stro ngest calculated interactions (up to -5.1
kcal/mol) are comparable with stacking interactions of saturated hydrogen-bridged rings
(-4.9 kcal/mol [1]) and stacking interactions between saturated hydrogen-bridged rings
and C6-aromatic rings (-4.4 kcal/mol [2]), as well as with hydrogen bonds between water
molecules (-4.8 kcal/mol [3]).
Results indicate that energies of stack ing interactions of resonance-assisted
hydrogen-bridged rings are not substantially different than energies of stacking
interactions between saturated hydrogen-bridged rings
JIMP 2 Software as a teaching tool: Understanding orbitals using fenskee-hall method
Teaching molecular orbital concept to undergraduate students is known to be very challenging; analysis of examination data for undergraduate students reveals that they do not have a clear understanding of the concepts of atomic and molecular orbitals (Tsaparlis, 1997). Understanding of the orbital concept has been subject to considerable debate and research (Barradas-Solas and Sánchez Gómez, 2014). One of teaching strategies to deal with this problem is based on usage of different quantum chemical software to calculate shape, energy and to visualize molecular orbitals. The main downside of this approach is the fact that quantum chemical calculations are often very
time-consuming, especially in the case of molecules that contain transition metal atoms. Fenske-Hall method is ab initio method mainly developed for molecular orbitals calculation of transition metal complexes and organometallic compounds (Hall and Fenske, 1972). It was shown that this method is very fast, and very accurate (results are similar to the results obtained by more rigorous and more time-consuming DFT methods). Here we present a series of computational laboratory exercises using Fenske-Hall method incorporated in Jimp2 software to calculate and visualize both atomic and molecular orbitals. Students will learn how to calculate energy and visualize molecular orbitals of simple molecules. Exercises provide deeper insight into relationship between atomic and molecular orbitals with special emphasis on calculation of contribution of atomic orbitals
in particular molecular orbital. Using results of Fenske-Hall calculations, students will construct molecular-orbital diagrams for simple molecules
Comparison of two views regarding the nature of the X-H…phenyl interaction
There are two approaches in the analysis of the nature of the X-H…phenyl interactions. One is based on the assumption that atoms, bonds and the π plane belonging to the phenyl ring, are the points which can be involved in the interaction. The other states that center of the phenyl ring is the point acceptor. In this paper we compare two views using the directionality of the X-H vector and length/angle correlations relative to both assumed point acceptors. The results suggest that on the basis of this methodology there is no clear answer regarding the nature of the acceptor site in the phenyl ring.Physical chemistry 2004 : 7th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 21-23 September 200
Supplementary data for the article: Malenov, D. P.; Hall, M. B.; Zarić, S. D. Influence of Metal Ion on Chelate–Aryl Stacking Interactions. International Journal of Quantum Chemistry 2018, 118 (16). https://doi.org/10.1002/qua.25629
Supplementary material for: [https://doi.org/10.1002/qua.25629]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2219
C − H···π interactions in the metal-porphyrin complexes with chelate ring as the h acceptor
Specific C − H···π interactions with the π-system of porphyrinato chelate ring were found in crystal structures of transition metal complexes from the CSD and statistical analysis of geometrical parameters for intramolecular and intermolecular interactions was done. DFT calculations on a model system show that energy of the interaction is 1.58 kcal/mol and that the strongest interaction occurs when the distance between hydrogen atom and the center of the chelate ring is 2.6 Å. This prediction is in good agreement with the distances for intermolecular interactions found in the crystal structures. In many cases the intramolecular interaction distances are much shorter than 2.6 Å, and these short distances appear to be caused by geometrical constrains. The C − H···π interactions with chelate ring of porphyrinato ligand can be important in biomolecules with porphyrin as they can influence the structure, contribute to the stability and play some role in function of biomolecules.Physical chemistry 2004 : 7th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 21-23 September 200
Supplementary material for the article: Blagojević, J. P.; Veljković, D.; Zarić, S. D. Stacking Interactions between Hydrogen-Bridged and Aromatic Rings: Study of Crystal Structures and Quantum Chemical Calculations. CrystEngComm 2017, 19 (1), 40–46. https://doi.org/10.1039/c6ce02045c
Supplementary material for:[https://doi.org/10.1039/c6ce02045c ]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2380]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3246
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