Related papers: An Expanded Gas-Grain Model for Interstellar Glyci…
Glycolaldehyde (HOCH$_2$CHO) and ethylene glycol ((CH$_2$OH)$_2$) are two complex organic molecules detected in the hot cores and hot corinos of several star-forming regions. The ethylene glycol/glycolaldehyde abundance ratio seems to show…
This paper will review the basic concepts of gas-phase and grain surface chemistry of dense molecular clouds, where low mass and high mass stars form. The chemistry of cold pre-stellar cloud cores, where molecular freeze-out and deuterium…
Understanding whether prebiotic molecules can endure and reform through the energetic stages of star formation is essential for tracing the continuity of interstellar chemistry toward life. Glycolamide, an isomer of glycine, was recently…
We have developed a model for molecular hydrogen formation under astrophysically relevant conditions. This model takes fully into account the presence of both physisorbed and chemisorbed sites on the surface, allows quantum mechanical…
An outstanding question of astrobiology is the link between the chemical composition of planets, comets, and other solar system bodies and the molecules formed in the interstellar medium. Understanding the chemical and physical evolution of…
We study the evolution of molecular hydrogen on the grain surfaces and in the gas phase using both the rate equation (which tracks the average number of molecules) and the master equation (which tracks the expectation values of molecules).…
Methyl formate, HCOOCH$_3$, and many of its isotopologues have been detected in astrophysical regions with considerable abundances. However, the recipe for the formation of this molecule and its isotopologues is not yet known. In this work,…
The molecular evolution that occurs in collapsing prestellar cores is investigated. To model the dynamics, we adopt the Larson-Penston (L-P) solution and analogues with slower rates of collapse. For the chemistry, we utilize the new…
Context. Cosmic ray particles that hit interstellar grains in dark molecular cores may induce whole-grain heating. The high temperature of a CR-heated grain allows energy barriers for bulk diffusion and reactions to be overcome.…
Amino acids are essential for the synthesis of protein. Amino acids contain both amine (R$-$NH$_{2}$) and carboxylic acid (R$-$COOH) functional groups, which help to understand the possible formation mechanism of life in the universe. Among…
We investigate the formation of the recently detected HNSO molecule using quantum chemical calculations on ices and astrochemical models in tandem. Our results indicate that HNSO is efficiently produced on grain surfaces through reactions…
Abridged: We detail and benchmark two sophisticated chemical models developed by the Heidelberg and Bordeaux astrochemistry groups. The main goal of this study is to elaborate on a few well-described tests for state-of-the-art astrochemical…
[Abridged] Ethylene oxide and its isomer acetaldehyde are important complex organic molecules because of their potential role in the formation of amino acids. Despite the fact that acetaldehyde is ubiquitous in the interstellar medium,…
A partial submillimeter line-survey was performed toward 7 high-mass young stellar objects (YSOs) aimed at detecting H2CO, CH3OH, CH2CO, CH3CHO, C2H5OH, HCOOH, HNCO and NH2CHO. In addition, other organic species such as CH3CN have been…
Many chemical models of dense interstellar clouds predict that the majority of gas-phase elemental nitrogen should be present as N2, with an abundance approximately five orders of magnitude less than that of hydrogen. As a homonuclear…
We discuss recent models of chemical evolution in the developing and collapsing protostellar envelopes associated with low-mass star formation. In particular, the effects of depletion of gas-phase molecules onto grain surfaces is…
It has been a long-standing problem to detect interstellar glycine (NH$_2$CH$_2$COOH), the simplest amino acid, in studying a possible relation between the Universe and origin of life. In the last about 40 years all surveys of glycine…
Context. Time dependent gas-grain chemistry can help us understand the layered structure of species deposited onto the surface of grains during the lifetime of a protoplanetary disk. The history of trapping important quantities of carbon-…
[Abridged] Planets and their atmospheres are built from gas and solid material in protoplanetary disks. This solid material grows from smaller, micron-sized grains to larger sizes in the disks, during the process of planet formation. Our…
A prevailing theory for the interstellar production of complex organic molecules (COMs) involves formation on warm dust-grain surfaces, via the diffusion and reaction of radicals produced through grain-surface photodissociation of stable…