The electron kinetic energy dependence of the photoelectron spectra and angular distributions of I(-)⋅CH(3)X (X=Cl,Br,I) cluster anions are measured via velocity mapped imaging at wavelengths between 350 and 270 nm. Processes analogous to those encountered in free CH(3)X-electron interactions are revealed. In particular, the presence and energies of resonances associated with a low lying σ(∗) state have a marked effect on the results of I(-)⋅CH(3)X photoexcitation. These effects (vibrational excitation, product anion production, and alteration of the photoelectron angular distribution) are far more prominent for I(-)⋅CH(3)I. However, in the vicinity of the (2)P(1/2) threshold there is a sharp deviation in the (2)P(3/2) channel angular distribution and an enhancement of the (2)P(3/2) channel vibrational structure of all three cluster anions. These latter effects are specific to the cluster anion environment through the relaxation of the partner excited I atom and subsequent electronic autodetachment.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1063/1.3487739 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Single layer TlX (X = Cl/Br/I) with a ferroelectric-valley coupling potential for an electrically tunable polarizer.
Phys Chem Chem Phys
December 2024
School of Science, Hebei University of Technology, Tianjin 300401, People's Republic of China.
Ferrovalley materials are generally hexagonal lattice systems with a ferromagnetism-valley coupling, in which the intrinsic ferromagnetism can induce valley polarization. However, as of now the number of ferrovalleys found is still limited. In this article, TlX (X = Cl/Br/I) single-layers (SLs) are proposed with a tetragonal lattice structure as well as ferroelectricity-valley coupling.
View Article and Find Full Text PDFHighly Stable MOF-Type Lead Halide Luminescent Ferroelectrics.
Angew Chem Int Ed Engl
July 2024
Shanghai Key Laboratory of Chemical Assessment and Sustain ability, School of Chemical Science and Engineering, Tongji University, 1239 Siping Rd., Shanghai, 200092, China.
Lead halide molecular ferroelectrics represent an important class of luminescent ferroelectrics, distinguished by their high chemical and structural tunability, excellent processability and distinctive luminescent characteristics. However, their inherent instability, prone to decomposition upon exposure to moisture and light, hinders their broader ferroelectric applications. Herein, for the first time, we present a series of isoreticular metal-organic framework (MOF)-type lead halide luminescent ferroelectrics, demonstrating exceptional robustness under ambient conditions for at least 15 months and even when subjected to aqueous boiling conditions.
View Article and Find Full Text PDFExperimental analysis of methylammonium and Formamidinium-based halide perovskite properties for optoelectronic applications.
Heliyon
November 2023
CSIR- National Physical Laboratory, Dr. KS Krishnan Marg, New Delhi, 110012, India.
Article Synopsis
- * This study investigates Formamidinium (FA)-based and Methylammonium (MA)-based bismuth halide perovskites using a technique called Ligand-Assisted Reprecipitation Technique (LARP), analyzing their structural and optical characteristics.
- * Results show varying band-gap values and crystal structures with different halide compositions, with potential implications for improving the efficiency of optoelectronic applications through simulations conducted in SCAPS-1D software.
Computational Studies of Coinage Metal Anion M + CHX (X = F, Cl, Br, I) Reactions in Gas Phase.
Molecules
January 2022
Key Laboratory of Cluster Science of Ministry of Education, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China.
We characterized the stationary points along the nucleophilic substitution (S2), oxidative insertion (OI), halogen abstraction (XA), and proton transfer (PT) product channels of M + CHX (M = Cu, Ag, Au; X = F, Cl, Br, I) reactions using the CCSD(T)/aug-cc-pVTZ level of theory. In general, the reaction energies follow the order of PT > XA > S2 > OI. The OI channel that results in oxidative insertion complex [CH-M-X] is most exothermic, and can be formed through a front-side attack of M on the C-X bond via a high transition state OxTS or through a S2-mediated halogen rearrangement path via a much lower transition state invTS.
View Article and Find Full Text PDFIntermolecular binding preferences of haloethynyl halogen-bond donors as a function of molecular electrostatic potentials in a family of -(pyridin-2-yl)amides.
Org Biomol Chem
August 2021
Department of Chemistry, Kansas State University, 213 CBC Building, 1212 Mid-Campus Dr North, Manhattan, KS 66506 - 0401, USA.
In order to explore how σ-hole potentials, as evaluated by molecular electrostatic potential (MEP) calculations, affect the ability of halogen atoms to engage in structure-directing intermolecular interactions, we synthesized four series of ethynyl halogen-substituted amide containing pyridines (activated targets); (N-(pyridin-2-yl)benzamides (Bz-act-X), N-(pyridin-2-yl)picolinamides (2act-X), N-(pyridin-2-yl)nicotinamides (3act-X) and N-(pyridin-2-yl) isonicotinamides (4act-X), where X = Cl/Br/I. The molecules are deliberately equipped with three distinctly different halogen-bond acceptor sites, π, N(pyr), and O[double bond, length as m-dash]C, to determine binding site preferences of different halogen-bond donors. Crystallographic data for ten (out of a possible twelve) new compounds were thus analyzed and compared with data for the corresponding unactivated species.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!