Bộ môn Vật lí Đại cương kính mời quý thầy cô, các bạn sinh viên dự Seminar khoa học:

Người trình bày: TS. Isabelle Kleiner

Inter-university of Atmospheric System Laboratory (LISA), CNRS, France

Thời gian: 15h00 Thứ 3, ngày 25 tháng 04 năm 2023

Địa điểm: Phòng họp Khoa Vật lí, 136 Xuân Thủy, Cầu Giấy, Hà Nội

Spectroscopy of molecules with astrophysical, atmospheric and biological interest

Abstract:

Spectroscopy and optical measurements are amongst the most powerful tools used by geophysicists and astrophysicists to obtain, at distance, information about the planetary atmospheres and about the interstellar medium. Morever, spectroscopy also allows us to determine molecular structures and to understand the intra-molecular interactions. The topic of our work concerned mainly molecules containing large amplitude motions and in particular molecules containing one or two methyl (CH3) internal rotors or inversion like in ammonia NH3.

One of the goals of our work is to model the line positions and intensities and to analyse the spectra for these molecules. That way we can provide reliable predictions of line positions and intensities for astrophysical molecules containing one internal rotor CH3, such as the isotopic species of methyl formate HCOOCH3, methanol CH3OH, acetaldehyde CH3CHO, acetamide CH3CONH2 or methyl acetate CH3-O-C(=O)-CH3, which has been recently detected in the interstellar cloud Orion thanks our prediction.

Another goal of our work is to get some knowledge of the structural properties of small organic molecules or biomimetic molecules. Fourier transform microwave spectroscopy in the gas phase coupled with high level quantum chemical calculations has recently led to the precise determination of molecular structures for the lowest energy conformers of a number of molecules. In this talk, I will show results for molecules with internal rotors, which are prototype for odorant molecules like linalool, an acyclic mono-terpene present in lavender and other plants and emitted in the earth atmosphere, important phytohormones produced by plants such as methyl jasmonate or some important nitrogen bearing pyrroles.