Results 31 to 40 of about 2,623 (182)

Energy Landscapes in Chemical Reactions and Transport

ChemPhysChem, Volume 26, Issue 6, March 15, 2025.
Kinetics/dynamics of chemical reactivity and transport of chemical species in a solid are both determined by the energy landscape in which they take place. Discussing common grounds but also distinct differences may help in advancing the understanding in both fields.
Karl‐Michael Weitzel
wiley   +1 more source

Deep Search for Phosphine in a Prestellar Core

The Astrophysical Journal Letters
Understanding in which chemical forms phosphorus exists in star- and planet-forming regions and how phosphorus is delivered to planets are of great interest from the viewpoint of the origin of life on Earth.
Kenji Furuya, Takashi Shimonishi
doaj   +1 more source

The Role of Terahertz and Far-IR Spectroscopy in Understanding the Formation and Evolution of Interstellar Prebiotic Molecules

Frontiers in Astronomy and Space Sciences, 2021
Stellar systems are often formed through the collapse of dense molecular clouds which, in turn, return copious amounts of atomic and molecular material to the interstellar medium.
Duncan V. Mifsud, Duncan V. Mifsud, Perry A. Hailey, Alejandra Traspas Muiña, Olivier Auriacombe, Nigel J. Mason, Sergio Ioppolo   +6 more
doaj   +1 more source

Thin‐film lithium niobate photonics: Frontiers in millimeter‐wave and terahertz generation and integrated applications

InfoScience, EarlyView.
With the advancement of 6G communications, high‐precision radar, and advanced imaging technologies, there is a growing demand for compact, high‐performance light sources capable of generating high‐frequency radio waves (millimeter‐wave and terahertz waves). This article systematically introduces how to efficiently generate these high‐frequency waves on
Jianfeng Xiong, Zhenyu Wang, Xu Li, Guo Tang, Sizhe Wang, Jiyuan Huang, Guochao Wang, Shuhua Yan, Wenzhao Sun   +8 more
wiley   +1 more source

A Framework for Incorporating Binding Energy Distribution in Gas-ice Astrochemical Models

The Astrophysical Journal
One of the most serious limitations of current astrochemical models with the rate equation (RE) approach is that only a single type of binding site is considered in grain surface chemistry, although laboratory and quantum chemical studies have found that
Kenji Furuya
doaj   +1 more source

Chemical Kinetics of 2‐, 4‐, and 2,4‐Seleno‐Uracils at Low Temperatures: Tautomerizations and Rotamerizations on Inert Matrices

International Journal of Chemical Kinetics, EarlyView.
ABSTRACT In the interstellar medium, chemical reactions proceed under conditions vastly different to those on Earth; these include extremely low temperatures and densities and take place in the gas phase and on water–ice grains. Understanding the energetics and more importantly the kinetics of such reactions is of relevance to the consequences on how ...
Judith Wurmel, John M. Simmie
wiley   +1 more source

Organic Chemistry in the H2-bearing, CO-rich Interstellar Ice Layer at Temperatures Relevant to Dense Cloud Interiors

The Astrophysical Journal
Ice chemistry in the dense, cold interstellar medium (ISM) is probably responsible for the formation of interstellar complex organic molecules (COMs). Recent laboratory experiments performed at T ∼ 4 K have shown that irradiation of CO:N _2 ice samples ...
Rafael Martín-Doménech, Alexander DelFranco, Karin I. Öberg, Mahesh Rajappan   +3 more
doaj   +1 more source

Size Matters: Barrier Heights and Widths in the Kinetics Of Tautomerisation and Rotamerisation of Thiotropolone and Its Five‐ and Three‐Membered Cyclic Analogues

International Journal of Chemical Kinetics, EarlyView.
ABSTRACT Recent experiments by Nunes et al. have demonstrated that unprecedented control of chemical reactions is possible by narrowband infrared vibrational photo‐excitation at low temperatures in inert matrices. The generated higher energy level conformers may then undergo rotamerisation and tautomerisation reactions which provide extremely useful ...
Judith Wurmel, John M. Simmie
wiley   +1 more source

Enantioselective Synthesis of a New Class of Stable and Functionalized Cyclopentadienes via CuH‐Catalysis

Angewandte Chemie, Volume 138, Issue 32, 3 August 2026.
Cyclopentadienes (CpHs) are fundamental building blocks with widespread applications in chemistry. However, their inherent acidity and isomeric instability have long limited access to chiral variants in an asymmetric fashion. Here, we introduce a CuH‐catalyzed asymmetric transformation that provides an unprecedented entry into a new class of ...
Piero Soppelsa, Riccardo Bellin, Besma Boulila, Francesco Vaghi, Manuel Orlandi   +4 more
wiley   +2 more sources

Cis–Trans Rotational Isomerism of Formic Acid, Sulfur, and Selenium Analogues and Their Dimers: Chemical Kinetics Under Interstellar Conditions

International Journal of Chemical Kinetics, EarlyView.
ABSTRACT We present chemical kinetic rate constants for the cis to trans isomerisation or rotamerization of monomeric seleno‐, thio‐, and formic acids and that of three of their dimeric species, based on variational transition state theory and multidimensional tunneling calculations in the gas‐phase, from 10 K to 300 K. These provide, firstly, reliable
Judith Wurmel, John M. Simmie
wiley   +1 more source