TY - JOUR

T1 - Theoretical prediction of structures, vibrational circular dichroism, and infrared spectra of chiral be4b8 cluster at different temperatures

AU - Buelna-García, Carlos Emiliano

AU - Robles-Chaparro, Eduardo

AU - Parra-Arellano, Tristan

AU - Quiroz-Castillo, Jesus Manuel

AU - Del-Castillo-Castro, Teresa

AU - Martínez-Guajardo, Gerardo

AU - Castillo-Quevedo, Cesar

AU - De-León-flores, Aned

AU - Anzueto-Sánchez, Gilberto

AU - Martin-Del-campo-solis, Martha Fabiola

AU - Mendoza-Wilson, Ana Maria

AU - Vásquez-Espinal, Alejandro

AU - Cabellos, Jose Luis

N1 - Publisher Copyright:
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.

PY - 2021/7/1

Y1 - 2021/7/1

N2 - Lowest-energy structures, the distribution of isomers, and their molecular properties depend significantly on geometry and temperature. Total energy computations using DFT methodology are typically carried out at a temperature of zero K; thereby, en-tropic contributions to the total energy are neglected, even though functional materials work at finite temperatures. In the present study, the probability of the occurrence of one particular Be4B8 isomer at temperature T is estimated by employing Gibbs free energy computed within the framework of quantum statistical mechanics and nanothermody-namics. To identify a list of all possible low-energy chiral and achiral structures, an ex-haustive and efficient exploration of the potential/free energy surfaces is carried out using a multi-level multistep global genetic algorithm search coupled with DFT. In addition, we discuss the energetic ordering of structures computed at the DFT level against single-point energy calculations at the CCSD(T) level of theory. The total VCD/IR spectra as a function of temperature are computed using each isomer’s probability of occurrence in a Boltzmann-weighted superposition of each isomer’s spectrum. Additionally, we present chemical bonding analysis using the adaptive natural density partitioning method in the chiral putative global minimum. The transition state structures and the enantiomer–en-antiomer and enantiomer–achiral activation energies as a function of temperature evidence that a change from an endergonic to an exergonic type of reaction occurs at a temperature of 739 K.

AB - Lowest-energy structures, the distribution of isomers, and their molecular properties depend significantly on geometry and temperature. Total energy computations using DFT methodology are typically carried out at a temperature of zero K; thereby, en-tropic contributions to the total energy are neglected, even though functional materials work at finite temperatures. In the present study, the probability of the occurrence of one particular Be4B8 isomer at temperature T is estimated by employing Gibbs free energy computed within the framework of quantum statistical mechanics and nanothermody-namics. To identify a list of all possible low-energy chiral and achiral structures, an ex-haustive and efficient exploration of the potential/free energy surfaces is carried out using a multi-level multistep global genetic algorithm search coupled with DFT. In addition, we discuss the energetic ordering of structures computed at the DFT level against single-point energy calculations at the CCSD(T) level of theory. The total VCD/IR spectra as a function of temperature are computed using each isomer’s probability of occurrence in a Boltzmann-weighted superposition of each isomer’s spectrum. Additionally, we present chemical bonding analysis using the adaptive natural density partitioning method in the chiral putative global minimum. The transition state structures and the enantiomer–en-antiomer and enantiomer–achiral activation energies as a function of temperature evidence that a change from an endergonic to an exergonic type of reaction occurs at a temperature of 739 K.

KW - Adaptive natural density partitioning method

KW - Be4B8

KW - Beryllium–boron cluster

KW - Boltzmann factors

KW - Density functional theory

KW - Enthalpy

KW - Entropy

KW - Genetic algorithm

KW - Gibbs free energy

KW - Global minimum

KW - IR spectra

KW - Nanothermodynamics

KW - Quantum statistical mechanics

KW - Tempera-ture

KW - Thermochemistry

KW - Vibrational circular dichroism

UR - http://www.scopus.com/inward/record.url?scp=85109519433&partnerID=8YFLogxK

U2 - 10.3390/molecules26133953

DO - 10.3390/molecules26133953

M3 - Artículo

C2 - 34203563

AN - SCOPUS:85109519433

SN - 1420-3049

VL - 26

JO - Molecules

JF - Molecules

IS - 13

M1 - 3953

ER -