Hydrocarbons are the central feedstock of fuels, solvents, lubricants, and the starting materials for many synthetic materials, and thus the physical properties of hydrocarbons have received intense study. Among these, the molecular flexibility and the power and infrared spectroscopies are the focus of this paper. These are examined for the linear alkane C14H30 using molecular dynamics (MD) calculations and recent machine-learned potentials. All MD calculations are microcanonical and start at the global linear minimum. The radius of gyration, the number of gauche bond conformations and the distributions of all C-C distances are reported as a function of the total internal energy and as a function of time. These are compared to the power spectra and to the double harmonic spectra of stationary points. Spectral features of the double harmonic spectra smoothly track structural differences, measured by the number of gauche conformations in the molecule. Preliminary calculations using the quantum local mode model for the CH-stretch are presented and satisfactorily capture anharmonic effects.

Dynamics Calculations of the Flexibility and Vibrational Spectrum of the Linear Alkane C14H30, Based on Machine-Learned Potentials [Dynamics Calculations of the Flexibility and Vibrational Spectrum of the Linear Alkane C₁₄H₃₀, Based on Machine-Learned Potentials] / C. Qu, P.L. Houston, R. Conte, J.M. Bowman. - In: JOURNAL OF PHYSICAL CHEMISTRY. A, MOLECULES, SPECTROSCOPY, KINETICS, ENVIRONMENT, & GENERAL THEORY. - ISSN 1089-5639. - 128:49(2024), pp. 10713-10722. [10.1021/acs.jpca.4c06943]

Dynamics Calculations of the Flexibility and Vibrational Spectrum of the Linear Alkane C14H30, Based on Machine-Learned Potentials [Dynamics Calculations of the Flexibility and Vibrational Spectrum of the Linear Alkane C₁₄H₃₀, Based on Machine-Learned Potentials]

R. Conte
Penultimo
;
2024

Abstract

Hydrocarbons are the central feedstock of fuels, solvents, lubricants, and the starting materials for many synthetic materials, and thus the physical properties of hydrocarbons have received intense study. Among these, the molecular flexibility and the power and infrared spectroscopies are the focus of this paper. These are examined for the linear alkane C14H30 using molecular dynamics (MD) calculations and recent machine-learned potentials. All MD calculations are microcanonical and start at the global linear minimum. The radius of gyration, the number of gauche bond conformations and the distributions of all C-C distances are reported as a function of the total internal energy and as a function of time. These are compared to the power spectra and to the double harmonic spectra of stationary points. Spectral features of the double harmonic spectra smoothly track structural differences, measured by the number of gauche conformations in the molecule. Preliminary calculations using the quantum local mode model for the CH-stretch are presented and satisfactorily capture anharmonic effects.
Settore CHEM-02/A - Chimica fisica
Settore PHYS-04/A - Fisica teorica della materia, modelli, metodi matematici e applicazioni
2024
3-dic-2024
Article (author)
File in questo prodotto:
File Dimensione Formato  
Publisher_Version.pdf

accesso aperto

Tipologia: Publisher's version/PDF
Dimensione 4.6 MB
Formato Adobe PDF
4.6 MB Adobe PDF Visualizza/Apri
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/1123961
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 0
  • ???jsp.display-item.citation.isi??? 0
social impact