INTERACTION BETWEEN Li<sup>+</sup> CATION WITH CROWN ETHERS OF Bz15C5, DBz16C5 AND DBz18C6: MOLECULAR MODELING BASE ON MNDO/d SEMIEMPIRICAL METHOD

The aim of this research is to find information about the substituent effect to the structure of crown ether benzo-15-crown-5 (Bz15C5), dibenzo-16-crown-5 (DBz16C5) and dibenzo-18-crown-6 (DBz18C6), and also crown ether selectivity to coordinate a Li+ metal cation. The presence of substituent could change the conformations flexibility of crown ether during interact with metal cation. In this research semi empirical MNDO/d method was used for calculations. Firstly, geometry optimization was conducted to crown ethers structure using MNDO/d methods. The next steps were running the geometry optimization of complexes between cation Li+ with crown ethers. Data were produced from these calculation are the parameter of crown ether structures, structures of the complexes, and the binding energy of the cation-crown ethers. The presence of electron-withdrawing substituents decreased the binding energy while that of electron-donating one increase the binding energy (value of ΔE more negative). The substituents which are increase the degree of symmetry of the cation-crown ether complexes could give the increase of crown ether selectivity to bind the cation. Selectivity of crown ether to bind the cation depends on the structural match between ionic radii of crown ether cavity (the ion-cavity size concept). Bz15C5 what has higher selectivity to bind Li+ than DBz16C5 and DBz18C6. Keywords: selectivity, crown ether, MNDO/d.

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MOLECULAR MODELLING OF Mn+.[DBz16C5] COMPLEXES, M = Li+, Na+ AND Zn2+ BASED ON MNDO/d SEMIEMPIRICAL METHOD

Indonesian Journal of Chemistry ◽

10.22146/ijc.21750 ◽

2010 ◽

Vol 6 (2) ◽

pp. 144-149

Author(s):

Harno Dwi Pranowo ◽

Chairil Anwar

Keyword(s):

Crown Ether ◽

Computational Chemistry ◽

Semiempirical Method ◽

Empirical Method ◽

Induction Effect ◽

Cation Selectivity ◽

Symmetrical Form ◽

Chemistry Calculation ◽

Semi Empirical ◽

Cation Complexes

The effect of substituent on dibenzo-16-crown-5 (DBz16C5) and interaction between these crown ether with metal cations was evaluated using computational chemistry calculations. Substituens where are connected to the benzene ring on the DBz16C5 are -COOH, -Br, -COOC2H5, -CHO, -CH=CHCO2H, -CH=CHCO2C2H5 and -CH(OH)CH3. The analysis based on computational chemistry calculation using MNDO/d semi empirical method was done. The first step is structure optimization of crown ether followed by optimization of crown ether-metals cation complexes Mn+.[DBz16C5], where M is Li+, Na+ and Zn2+. Interactions of the crown ether and cation were discussed in term of the structure parameter of crown ether, atomic charges and energy interaction of the crown ether-metals cation. Electron donating groups increase the capability of crown ether to bind cation by means of induction effect, while electron withdrawing groups reduce the ability of crown ether to bind cation. Any substituent on the benzene in DBz16C5 which can be make the symmetrical form of the crown ether-metals cation complexes will increase the selectivity of the crown ether to bind the cation. Selectivity of the crown ether to bind cation also depends on the compatibility of the diameter of cation and cavity of crown ether. DBz16C5 has higher selectivity to bind the Na+ compare to the Li+ and Zn2+. Keywords: selectivity, dibenzo-16-crown-5, MNDO/d

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THEORETICAL STUDY OF THE EFFECT OF WATER MOLECULE ADDITION ON THE CONFORMATION OF SUBSTITUTED DIBENZO-18-CROWN-6 ETHER IN ITS COMPLEXATION WITH Na+ CATION USING SEMI EMPIRICAL METHOD MNDO/d

Indonesian Journal of Chemistry ◽

10.22146/ijc.21894 ◽

2010 ◽

Vol 3 (2) ◽

pp. 111-117

Author(s):

Harno Dwi Pranowo ◽

Tuti Hartati Siregar ◽

Mudasir Mudasir

Keyword(s):

Binding Energy ◽

Water Molecule ◽

Metal Ion ◽

Geometry Optimization ◽

Semiempirical Method ◽

Empirical Method ◽

Trial And Error ◽

Effect Of Water ◽

The Stability ◽

Semi Empirical

The effect of water molecule addition into modeling structure of complex of substituted dibenzo-18-crown-6 ether with metal ion Na+ was studied. The aim of this research is to find information about geometrical conformation of substituted DB18C6 and its selectivity to complex/coordinate metal ion Na+ in the presence of water molecule. In this research semi empirical method was used for calculation. To find the best conformation, trial and error experiments were conducted using semi empirical method available in HyperChem 6.0, finally MNDO/d method was selected. The result of geometry optimization showed that addition of water molecule improve the stability of the conformation of substituted DB18C6 and increase the selectivity of this compound to complex metal ion Na+. The presence of electron-withdrawing substituents decreased the binding energy while that of electron-donating one increase the binding energy (value of DE more negative). Cavity radii of DB18C6 in the presence of water molecule extended from 2.3 Å to 2.6 Å. This figure is almost similar to that of experimental data. Keywords: Crown ether, molecular modelling, semiempirical method

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Crown ethers in hydrogenated graphene

Physical Chemistry Chemical Physics ◽

10.1039/d1cp03069h ◽

2021 ◽

Author(s):

Kai Guo ◽

Sitong Liu ◽

Haoming Tu ◽

Zhikun Wang ◽

Liang Chen ◽

...

Keyword(s):

Crown Ether ◽

Crown Ethers ◽

Hydrogenated Graphene ◽

High Flexibility

Crown ethers could serve as hosts to selectively incorporate various guest atoms or molecules within the macrocycles. However, the high flexibility of crown ether molecules limits their applications in areas...

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Conformational effect on the preferential binding of alkali metal cation with crown ether: A molecular level investigation

Desalination and Water Treatment ◽

10.5004/dwt.2009.947 ◽

2009 ◽

Vol 12 (1-3) ◽

pp. 93-99 ◽

Cited By ~ 5

Author(s):

Sulagna De ◽

Sk. Musharaf Ali ◽

M.R.K. Shenoi ◽

Sandip K. Ghosh ◽

Dilip K. Maity

Keyword(s):

Crown Ether ◽

Alkali Metal ◽

Metal Cation ◽

Molecular Level ◽

Alkali Metal Cation ◽

Conformational Effect ◽

Preferential Binding

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New Application of Crown Ether. V. The Effect of Crown Ethers on the Acid–Base Interaction between 2,4,4′,6-Tetranitrodiphenylamine and Primary Amines in Benzene

Bulletin of the Chemical Society of Japan ◽

10.1246/bcsj.54.458 ◽

1981 ◽

Vol 54 (2) ◽

pp. 458-461 ◽

Cited By ~ 7

Author(s):

Fumio Wada ◽

Yoshiko Wada ◽

Kiyoshi Kikukawa ◽

Tsutomu Matsuda

Keyword(s):

Crown Ether ◽

Crown Ethers ◽

Primary Amines ◽

Acid Base ◽

Base Interaction ◽

Acid Base Interaction

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ChemInform Abstract: f-Element/Crown Ether Complexes. Part 10. Oxidation of UCl4 to (UO2Cl4)2- in the Presence of Crown Ethers: Structural Characterization of Crown Ether Complexed Ammonium Ions ((NH4)(15-crown-5)2)2(UO2Cl4)·2 CH3CN, ((NH4)(benzo-15-crown

ChemInform ◽

10.1002/chin.198816280 ◽

1988 ◽

Vol 19 (16) ◽

Author(s):

R. D. ROGERS ◽

L. K. KURIHARA ◽

M. M. BENNING

Keyword(s):

Crown Ether ◽

Crown Ethers ◽

Structural Characterization ◽

Ammonium Ions ◽

Crown Ether Complexes

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Universal origin of heavy elements

10.21203/rs.3.rs-440633/v1 ◽

2021 ◽

Author(s):

Jose Orce ◽

Balaram Dey ◽

Cebo Ngwetsheni ◽

Brenden Lesch ◽

Andile Zulu ◽

...

Keyword(s):

Binding Energy ◽

Symmetry Energy ◽

Neutron Capture ◽

Decay Rates ◽

Heavy Elements ◽

Capture Process ◽

Atomic Nuclei ◽

Radiative Neutron ◽

Radiative Neutron Capture ◽

Semi Empirical

Abstract The abundance of heavy elements above iron through the rapid neutron capture process or r-process is intimately related to the competition between neutron capture and $\beta$ decay rates, which ultimately depends on the binding energy of atomic nuclei. The well-known Bethe-Weizsacker semi-empirical mass formula describes the binding energy of ground states in nuclei with temperatures of T~0 MeV, where the nuclear symmetry energy saturates between 23-26 MeV. Here we find a larger saturation energy of ~30 MeV for nuclei at T~0.7-1.3 MeV, which corresponds to the typical temperatures where seed elements are created during the cooling down of the ejecta following neutron-star mergers and collapsars. This large symmetry energy yields a reduction of the binding energy per nucleon for neutron-rich nuclei; hence, the close in of the neutron dripline, where nuclei become unbound. This finding constrains exotic paths in the nucleosynthesis of heavy elements -- as supported by microscopic calculations of radiative neutron-capture rates -- and further supports the universal origin of heavy elements, as inferred from the abundances in extremely metal-poor stars and meteorites.

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