Assessment, validation and interpretation of the absolute infrared intensities of the vibrational bands of chlorofluoromethanes

• Grant number: 16/07411-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2016
• End date: December 31, 2017
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Roy Edward Bruns
• Grantee: Leonardo José Duarte
• Host Institution: Instituto de Química (IQ). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

The interest in studying the effects of gases that cause the greenhouse effect motivated the development of an extensive database containing several infrared spectra obtained through high resolution techniques. In this database there are present the spectra of tens of halomethanes with a resolution as high as of 0.1 cm-1, a class of molecules that have been already studied by our group for some years. In order for the band intensities obtained from these spectra be able to used as a reference for other groups, a simple numerical integration must be carried out. This task, however, proves to be extremely laborious as the data volume is quite large and there is not a free intuitive software available that can perform that operation. This project proposes to solve that problem by developing an open-source program that performs the required numerical integration of the spectra using an automatic algorithm. The software should be available in an accessible manner for the entire academic community. The interest in studying the effects of gases that cause the greenhouse effect motivated the development of an extensive database containing several infrared spectra obtained through high resolution techniques. In this database there are present the spectra of tens of halomethanes with a resolution as high as of 0.1 cm-1, a class of molecules that have been already studied by our group for some years. In order for the band intensities obtained from these spectra be able to used as a reference for other groups, a simple numerical integration must be carried out. This task, however, proves to be extremely laborious as the data volume is quite large and there is not a free intuitive software available that can perform that operation. This project proposes to solve that problem by developing an open-source program that performs the required numerical integration of the spectra using an automatic algorithm. The software should be available in an accessible manner for the entire academic community. In addition, it is proposed to use these newly obtained experimental to verify the accuracy of a classic empirical electronegativity model. The intensities of all bands located between 600 and 4000 cm-1 from the PNNL database are to be determined for 30 at least halomethanes.

Scientific publications

(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)

DUARTE, LEONARDO J.; SILVA, ARNALDO F.; RICHTER, WAGNER E.; BRUNS, ROY E.. FTIR and dispersive gas phase fundamental infrared intensities of the fluorochloromethanes: Comparison with QCISD/cc-pVTZ results. SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY, v. 205, p. 269-275, DEC 5 2018. (16/07411-4, 14/21241-9)

DUARTE, LEONARDO J.; RICHTER, WAGNER E.; SILVA, ARNALDO F.; BRUNS, ROY E.. Quantum Theory of Atoms in Molecules Charge-Charge Transfer-Dipolar Polarization Classification of Infrared Intensities. Journal of Physical Chemistry A, v. 121, n. 42, p. 8115-8123, OCT 26 2017. (16/07411-4, 14/21241-9)

SILVA, ARNALDO F.; DUARTE, LEONARDO J.; BRUNS, ROY E.. QTAIM-Based Characteristic Group Infrared Intensities of Amino Acids and Their Transference to Peptides. Journal of Physical Chemistry A, v. 120, n. 42, p. 8387-8399, OCT 27 2016. (14/21241-9, 16/07411-4, 09/09678-4)