Spectroscopic characterization of radicals formed by hydrogen-atom abstraction from γ-valerolactone and γ-butyrolactone.

γ-valerolactone (GVL) and its unmethylated counterpart, γ-butyrolactone (GBL), are important compounds with a wide range of potential uses. For example, GVL is proposed as an ideal alternative renewable energy source, while GBL can be utilized as an electrolyte. Understanding the combustion mechanisms of these compounds is crucial for optimizing their use as energy sources and monitoring the products formed during combustion.

Hydrogen-atom-assisted processes on thioacetamide in -H matrix - formation of thiol tautomers.

TA has been isolated in low-temperature -H matrices and it has been exposed to H atoms. In accordance with previous experimental results, TA exclusively exists in its more stable thione tautomeric form in the freshly deposited matrix. However, upon H atom generation, the bands belonging to the precursor start decreasing with the simultaneous appearance of new bands.

UV photolysis of thiourea and its -methylated derivative in cryogenic matrices.

Exploration of the photolytic dynamics of sulfurous compounds is essential, eventually contributing not only to our comprehension of their fundamental organic chemistry but also shedding light on astrophysical implications. This study aims to investigate two astrochemically relevant sulfur-containing molecules, namely, thiourea (TU) and its -methylated counterpart, -methyl thiourea (NMTU), in cryogenic matrices. These molecules were deposited both in solid Ar and in a quantum host, specifically in solid -H matrices, with the latter exhibiting unique properties.

Energetic processing of thioacetamide in cryogenic matrices.

There is an ongoing debate on the apparent depletion of sulfur in the interstellar medium (ISM) compared to its universal abundance; therefore, the investigation of sulfurous compounds at low temperatures is of utmost importance. This work aims to study thioacetamide, H3C-C(=S)-NH2, in low-temperature inert Ar and para-H2 matrices by IR spectroscopy. The samples have been exposed to various sources of irradiation, such as Lyman-α or laser UV photons as well as energetic electrons.

Potential Catalytic Role of Small Heterocycles in Interstellar H Formation: A Laboratory Astrochemistry Study on Furan and Its Hydrogenated Forms.

It is now well-accepted in astrochemistry that the formation of interstellar H is taking place on the surface of interstellar grains. It has also been suggested a long time ago that polyaromatic hydrocarbons (PAHs) can catalyze this process by subsequent H atom addition and H abstraction reactions. Recent quantum chemical computations suggested that small heterocycles can be better catalysts than PAHs.

Non-energetic, Low-Temperature Formation of C-Glycyl Radical, a Potential Interstellar Precursor of Natural Amino Acids.

The reaction of H atoms with glycine was investigated at 3.1 K in -H, a quantum-solid host. The reaction was followed by IR spectroscopy, with the spectral analysis aided by quantum chemical computations.