Implementation of a combined Hessian technique for obtaining VCD spectra

• Grant number: 16/23165-3
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Start date: March 01, 2017
• End date: February 28, 2018
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Sergio Emanuel Galembeck
• Grantee: Tiago Quevedo Teodoro
• Supervisor: Lucas Visscher
• Host Institution: Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto (FFCLRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Institution abroad: University Amsterdam (VU), Netherlands
• Associated to the scholarship: 16/07787-4 - Development of a computational toolbox for the analysis of chiral molecular systems using vibrational circular dichroism, BP.PD

Abstract

Vibrational spectroscopy is one of the most important tools for characterizing the structure of molecules. An example is the Vibrational Circular Dichroism (VCD), the infrared circular dichroism due to vibrations of chiral molecules. One way to reproduce the vibrational spectrum and to provide frequencies and normal modes is known as the Normal Mode Analysis (NMA), which requires the diagonalization of the mass-weighted Hessian matrix. The latter matrix addresses the second derivative of the potential energy surface with respect to atomic displacements. However, such approach can be problematic when large molecules, such as proteins, are analysed due to the significant computational demand associated with the construction of the Hessian. In the present project we intend to tackle this issue by developing an efficient computational code that provides the user with the possibility of partitioning the molecule into smaller fragments through a graphical user interface. These fragments are then treated separately as, e.g., the Hessian respective to the active chiral fragment of the system could be obtained at a higher level of theory than the remaining fragments. This sub-system technique will be evaluated for a set of molecules with pharmaceutical interest, such as the Abbott library, along with other partial Hessian techniques already available in the literature. The implementation of the code as a sub-routine in a main code such as the Amsterdam Density Functional (ADF) package will provide an alternative to obtain VCD spectra for larger systems than what can be currently studied. (AU)

Scientific publications

(5)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

GRIMMEL, STEPHANIE A.; TEODORO, TIAGO Q.; VISSCHER, LUCAS. Is it worthwhile to go beyond the local-density approximation in subsystem density functional theory?. International Journal of Quantum Chemistry, DEC 2019. (16/07787-4, 16/23165-3)

TEODORO, T. Q.; KOENIS, M. A. J.; RUGER, R.; GALEMBECK, S. E.; BUMA, W. J.; NICU, V. P.; VISSCHER, L.. Use of Density Functional Based Tight Binding Methods in Vibrational Circular Dichroism. Journal of Physical Chemistry A, v. 122, n. 49, p. 9435-9445, DEC 13 2018. (16/07787-4, 14/50265-3, 16/23165-3, 08/02677-0)

TEODORO, T. Q.; KOENIS, M. A. J.; GALEMBECK, S. E.; NICU, V. P.; BUMA, W. J.; VISSCHER, L.. Frequency Range Selection Method for Vibrational Spectra. Journal of Physical Chemistry Letters, v. 9, n. 23, p. 6878-6882, DEC 6 2018. (16/07787-4, 14/50265-3, 16/23165-3, 08/02677-0)

GRIMMEL, STEPHANIE A.; TEODORO, TIAGO Q.; VISSCHER, LUCAS. Is it worthwhile to go beyond the local-density approximation in subsystem density functional theory?. International Journal of Quantum Chemistry, v. 120, n. 21, p. 11-pg., 2019-12-11. (16/07787-4, 16/23165-3)

GRIMMEL, STEPHANIE A.; TEODORO, TIAGO Q.; VISSCHER, LUCAS. Is it worthwhile to go beyond the local-density approximation in subsystem density functional theory?. International Journal of Quantum Chemistry, v. 120, n. 21, SI, NOV 1 2020. (16/07787-4, 16/23165-3)