Relative Populations and IR Spectra of Cu Cluster at Finite Temperature Based on DFT and Statistical Thermodynamics Calculations.

The relative populations of Cu isomers depend to a great extent on the temperature. Density functional theory and nanothermodynamics can be combined to compute the geometrical optimization of isomers and their spectroscopic properties in an approximate manner. In this article, we investigate entropy-driven isomer distributions of Cu clusters and the effect of temperature on their IR spectra.

Effects of Temperature on Enantiomerization Energy and Distribution of Isomers in the Chiral Cu Cluster.

In this study, we report the lowest energy structure of bare Cu nanoclusters as a pair of enantiomers at room temperature. Moreover, we compute the enantiomerization energy for the interconversion from minus to plus structures in the chiral putative global minimum for temperatures ranging from 20 to 1300 K. Additionally, employing nanothermodynamics, we compute the probabilities of occurrence for each particular isomer as a function of temperature.

Theoretical Prediction of Structures, Vibrational Circular Dichroism, and Infrared Spectra of Chiral BeB Cluster at Different Temperatures.

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, entropic 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 BeB isomer at temperature T is estimated by employing Gibbs free energy computed within the framework of quantum statistical mechanics and nanothermodynamics.