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9. Metallaborazines: To Be or Not To Be Delocalized

Author

Islas, Rafael, primary, Arias-Olivares, David, additional, Becerra-Buitrago, Andrés, additional, García-Sánchez, Luis Carlos, additional, Méndez-Ayón, Lya Neftaly, additional, and Zuniga-Gutierrez, Bernardo, additional

Published
2021
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13. Analysis of the electronic delocalization in some B12´s isoelectronic analogues doped with beryllium and/or carbon

Author

Islas, Rafael, Inostroza, Diego, Arias Olivares, David, Zúñiga Gutiérrez, Bernardo, Poater i Teixidor, Jordi, Solà i Puig, Miquel, and Ministerio de Economía y Competitividad (Espanya)

Subjects
Orbitals moleculars, Molecular orbitals, Aromaticitat (Química), Aromaticity (Chemistry), Deslocalització electrònica, Electronic delocalization
Abstract

In the current work, a new family of isoelectronic analogues to B12 is reported. The construction of this family was performed through the isoelectronic substitution principle to generate species such as B11C+, B11Be-, B10BeC, B10C22+, B10Be22- B9Be2C-, and B9BeC2+. The search for the global minimum was realized employing genetic algorithms, while the induced magnetic field, electronic localization function, magnetic current densities, and multicenter aromaticity criteria were calculated to understand their electronic delocalization. Our results show that, in general, C atoms avoid hypercoordination, whereas we have found species with Be atoms located in hypercoordinated positions that are relatively stable. Our analysis of aromaticity indicates that B12 has double and disk aromaticity. Mono, double or triple substitution of B by C+ or Be- reduces somewhat the aromaticity of the clusters, but less in the case of Be- substitution RI is grateful with Fondecyt 11160927 and Fondecyt 1201436 projects for the financial supporting. DI is grateful for the financial support by CONICYT PFCHA/DOCTORADO NACIONAL/2019 – 21190427. BZ-G acknowledges the financial support given by Conacyt Project (258647). This work has also been supported by the Ministerio de Economía y Competitividad (MINECO) of Spain (Projects CTQ2017-85341-P, CTQ2016-77558-R, and MDM-2017- 0767) and the Generalitat de Catalunya (projects 2017SGR39 and 2017SGR348, Xarxa de Referència en Química Teòrica i Computacional, and ICREA Academia 2014 prize for M.S.)

Published
2020

14. Analysis in silico of chemical reactivity employing the local hyper‐softness in some classic aromatic compounds, boron aromatic clusters and all‐metal aromatic clusters.

Author

Martínez‐Araya, Jorge I. and Islas, Rafael

Subjects
*ANALYTICAL chemistry, *MOLECULAR shapes, *ELECTRIC potential, *IONIC interactions, *BORON, *BORON steel, *AROMATIC compounds
Abstract

In the current work, the authors analyzed and compared the chemical behavior of some (anti)aromatic compounds. The species selected are benzene and cyclobutadiene as the aromatic and antiaromatic classical examples, respectively. Next, the anion Al42−, which is the first all‐metal molecule catalogued as aromatic and its non‐metallic isoelectronic analog, B42− were also analyzed. The antiaromatic clusters Al44− and B44− were studied in form of lithium salts. And the end, the non‐planar B12 boron cluster and its isoelectronic analogs (B11Be− and B11C+) were considered for being analyzed under the same criterium. The analysis was realized employing the following descriptors: molecular electrostatic potential and local hyper‐softness to get insights concerning local reactivity when facing reagents leading to ionic or covalent interactions. The results show that all the molecules analyzed presented some specific variations in their respective local reactivity despite being labeled as aromatic compounds. This analysis provides a notion that the local reactivity is more based on the nature of the atoms and the molecular geometry than the aromatic character by itself. [ABSTRACT FROM AUTHOR]

Published
2022
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18. Analysis of the electronic delocalization in some isoelectronic analogues of B12 doped with beryllium and/or carbon.

Author

Islas, Rafael, Inostroza, Diego, Arias-Olivares, David, Zúñiga-Gutiérrez, Bernardo, Poater, Jordi, and Solà, Miquel

Abstract

In the current work, a new family of isoelectronic analogues to B12 is reported. The construction of this family was performed through the isoelectronic substitution principle to generate species such as B11C+, B11Be−, B10BeC, B10C22+, B10Be22− B9Be2C−, and B9BeC2+. The search for the global minimum was realized by utilizing genetic algorithms, while the induced magnetic field, electronic localization function, magnetic current densities, and multicenter aromaticity criteria were calculated to understand their electronic delocalization. Our results show that, in general, C atoms avoid hypercoordination, whereas we have found species with Be atoms located in hypercoordinated positions that are relatively stable. Our analysis of aromaticity indicates that B12 has double σ and π disk aromaticity. Mono, double or triple substitution of B by C+ or Be− reduces somewhat the aromaticity of the clusters, but less in the case of Be− substitution. [ABSTRACT FROM AUTHOR]

Published
2020
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22. Designing 3-D molecular stars

Author

Tiznado, William, Perez-Peralta, Nancy, Islas, Rafael, Toro-Labbe, Alejandro, Ugalde, Jesus M., and Merino, Gabriel

Subjects
Ligands -- Chemical properties, Ligands -- Thermal properties, Lithium alloys -- Chemical properties, Lithium alloys -- Thermal properties, Pauli exclusion principle -- Analysis, Silicon alloys -- Chemical properties, Silicon alloys -- Structure, Chemistry
Abstract

The potential energy surfaces of the [Si.sub.5][Li.sub.n.sup.5-6] (n = 5?7) systems were explored in detail to find feasible way to design three-dimensional star-like silicon structures using the appropriate ligands. The calculation results revealed that the important contribution of ionic character of the Si-Li interactions to induce the formation of a bridged structure and the contribution of reduction of the Pauli repulsion and the maximization of the orbital towards formation of star-like structure.

Published
2009

23. Planar tetracoordinate carbons in cyclic semisaturated hydrocarbons

Author

Perez-Peralta, Nancy, Sanchez, Mario, Martin-Polo, Jesus, Islas, Rafael, Vela, Alberto, and Merino, Gabriel

Subjects
Hydrocarbons -- Electric properties, Carbon compounds -- Electric properties, Biological sciences, Chemistry
Abstract

The [C.sub.5.sup.2-] skeleton in combination with saturated hydrocarbon fragments is used to obtain a series of planar tetracoordinate carbon molecules in cyclic semisaturated hydrocarbons. The system is the first example of semisaturated cycles containing a planar tetracoordinate carbon stabilized only by electronic factors.

Published
2008

24. Boron rings enclosing planar hypercoordinate group 14 elements

Author

Islas, Rafael, Heine, Thomas, Keigo Ito, Schleyer, Paul v. R., and Merino, Gabriel

Subjects
Chemical bonds -- Analysis, Nuclear magnetic resonance spectroscopy -- Technology application, Organoboron compounds -- Structure, Organoboron compounds -- Chemical properties, Technology application, Chemistry
Abstract

The article discusses the designing of different sets of boron rings enclosing the planar hypercoordinate group 14 elements on the basis of the geometrical and electronic fit principles. The set is designed in a way that the boron ring can accommodate the central atom easily.

Published
2007

26. Analysis of the aromaticity in extended systems formed from isoelectronic Al42− and C42+ aromatic clusters.

Author

Islas, Rafael, Oyarzún, Diego P., and Cantero-López, Plinio

Subjects
AROMATICITY, ALUMINUM, CARBON-carbon bonds, ISOMERS, GENETIC algorithms
Abstract

Inspired by carbo-benzene and its inorganic analogues, in the current work, the viability of extended systems (called carbomers) formed from aromatic small rings was studied. The aluminum aromatic cluster, Al42−, and its isoelectronic carbon analogue, C42+, were employed as starting point. The insertion of alkynyl units into the Al-Al and C-C bonds results in the extended molecules named carbomers. These molecules were compared with the global minima structures, which were searched employing the genetic algorithm program, GEGA. The electronic delocalization (aromaticity) of the isomers was studied with the induced magnetic field (Bind). The results showed that global minimum of C122+ (formed from C42+) was an unexpected diatropic structure which presented a similar magnetic response to the C42+ cluster. Also, optical properties of C122+ were computed. [ABSTRACT FROM AUTHOR]

Published
2018
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28. Simple and Rapid One‐Step Electrochemical Synthesis of Nanogranular Cu2O Films.

Author

Oyarzún, Diego P., Broens, Martín I., Linarez Pérez, Omar E., López Teijelo, Manuel, Islas, Rafael, and Arratia‐Perez, Ramiro

Abstract

Abstract: In the present work, we report a simple experimental strategy for the one‐step electrochemical synthesis of nanogranular Cu2O films by copper anodization in fluoride‐containing ethylene glycol media. Microscopic exploration using field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM) and transmission electron microscopy (TEM), shows the formation of spherical shape grains with sizes ranging from 20 to 40 nm. Raman and X‐Ray Photoemission Spectroscopy (XPS) results indicate that only CuI oxide is obtained. A band gap energy Eg=2.01 eV is estimated from UV–vis reflectance spectroscopy indicating that an indirect transition mechanism between semiconductor bands takes place. These evidences indicate that the present synthesis of nanogranular Cu2O films is a promising method for obtaining improved properties of materials for the design of photoelectronic devices. [ABSTRACT FROM AUTHOR]

Published
2018
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29. Dynamical behavior of Borospherene: A Nanobubble

Author

Martínez-Guajardo, Gerardo, primary, Luis Cabellos, José, additional, Díaz-Celaya, Andres, additional, Pan, Sudip, additional, Islas, Rafael, additional, Chattaraj, Pratim K., additional, Heine, Thomas, additional, and Merino, Gabriel, additional

Published
2015
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34. Impacto de la mercadotecnia en Pymes dedicadas a la comercialización de ropa y accesorios en 5 municipios del estado de Tlaxcala.

Author

López Islas, Rafael, Vázquez Morales, Irma, Rivera Juárez, Karla Samira, López Islas, Andrés, and Montiel Huerta, Maria Elizabeth

Abstract

Copyright of Congreso Internacional de Investigacion Academia Journals is the property of PDHTech, LLC and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2016

35. The inorganic analogues of carbo -benzene

Author

Jalife, Said, primary, Audiffred, Martha, additional, Islas, Rafael, additional, Escalante, Sigfrido, additional, Pan, Sudip, additional, Chattaraj, Pratim K., additional, and Merino, Gabriel, additional

Published
2014
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36. Stop rotating! One substitution halts the B19−motor

Author

Cervantes-Navarro, Francisco, primary, Martínez-Guajardo, Gerardo, additional, Osorio, Edison, additional, Moreno, Diego, additional, Tiznado, William, additional, Islas, Rafael, additional, Donald, Kelling J., additional, and Merino, Gabriel, additional

Published
2014
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37. Carbo-Cages: A Computational Study

Author

Azpiroz, Jon M., primary, Islas, Rafael, additional, Moreno, Diego, additional, Fernández-Herrera, María A., additional, Pan, Sudip, additional, Chattaraj, Pratim K., additional, Martínez-Guajardo, Gerardo, additional, Ugalde, Jesus M., additional, and Merino, Gabriel, additional

Published
2014
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42. Boron avoids cycloalkane-like structures in the LinBnH2n series.

Author

Vásquez-Espinal, Alejandro, Torres-Vega, Juan J., Alvarez-Thon, Luis, Fuentealba, Patricio, Islas, Rafael, and Tiznado, William

Subjects
BORON, CYCLOALKANES, CARBOCATIONS, HUCKEL molecular orbitals, CHEMICAL bonds, GAS phase reactions
Abstract

The stability of the LinBnH2n (n = 3–6) series was analyzed using quantum chemical calculations, and it was found that cyclic isomers are not energetically favored. This is different to what happens in their organic counterparts (CnH2n), where cyclopentane (C5H10) and cyclohexane (C6H12) are the low-lying isomers. Apparently, aromaticity is a key-stabilizing factor that needs to be considered for designing stable lithium-boron hydride analogues of cyclic organic compounds. This is verified in the Li3B3H3+ system, which has been designed as the smallest aromatic carbocation (C3H3+) analogue. The global minimum structure of Li3B3H3+ contains a triangular B3H32− moiety, which has structural and chemical bonding features similar to its organic counterpart. Besides, this new cluster is classified as aromatic according to both the 4n + 2 Hückel rule and the analysis of the induced magnetic field. This theoretical evidence leads us to propose this cluster as a viable target for experimental detection in the gas phase. [ABSTRACT FROM AUTHOR]

Published
2016
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47. ChemInform Abstract: Starlike Aluminum-Carbon Aromatic Species.

Author

Wu, Yan-Bo, primary, Jiang, Jin-Liang, additional, Lu, Hai-Gang, additional, Wang, Zhi-Xiang, additional, Perez-Peralta, Nancy, additional, Islas, Rafael, additional, Contreras, Maryel, additional, Merino, Gabriel, additional, Wu, Judy I-Chia, additional, and von Rague Schleyer, Paul, additional

Published
2011
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48. Starlike Aluminum–Carbon Aromatic Species

Author

Wu, Yan‐Bo, primary, Jiang, Jin‐Liang, additional, Lu, Hai‐Gang, additional, Wang, Zhi‐Xiang, additional, Perez‐Peralta, Nancy, additional, Islas, Rafael, additional, Contreras, Maryel, additional, Merino, Gabriel, additional, Wu, Judy I‐Chia, additional, and von Ragué Schleyer, Paul, additional

Published
2010
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