easyPARM: Automated, Versatile, and Reliable Force Field Parameters for Metal-Containing Molecules with Unique Labeling of Coordinating Atoms

Journal of Chemical Theory and Computation, Год журнала: 2025, Номер unknown

Опубликована: Фев. 6, 2025

The dynamics of metal centers are challenging to describe due the vast variety ligands, metals, and coordination spheres, hampering existence general databases transferable force field parameters for classical molecular simulations. Here, we present easyPARM, a Python-based tool that can calculate wide range complexes from routine frequency calculations with electronic structure methods. approach is based on unique labeling strategy, in which each ligand atom coordinates receives type. This design prevents parameter shortage, duplication, necessity post-process output files, even very complicated whose parametrization process remain automatic. program requires Cartesian Hessian matrix, geometry xyz file, atomic charges provide reliable force-field extensively benchmarked against density functional theory both gas condensed phases. procedure allows description at low computational cost an accuracy as good quality matrix obtained by quantum chemistry easyPARM v2.00 reads vibrational frequencies Gaussian (version 09 or 16) ORCA 5 6) format provides refined Amber format. These be directly used NAMD engines converted other formats. available free charge GitHub platform (https://github.com/Abdelazim-Abdelgawwad/easyPARM.git).

Язык: Английский

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Electrostatic Work Causes Unexpected Reactivity in Ionic Photoredox Catalysts in Low Dielectric Constant Solvents

The Journal of Physical Chemistry B, Год журнала: 2025, Номер unknown

Опубликована: Апрель 3, 2025

We show that in low dielectric constant (εr) solvents, the prototypical cationic photoredox catalyst [Ir(III)(dFCF3ppy)2-(5,5'-dCF3bpy)]+ is capable of oxidizing its counterion an unexpected photoinduced electron transfer (PET) process. Photoinduced oxidation tetrakis[3,5-bis(trifluoromethyl)phenyl]borate (abbv. [BAr4F]-) anion leads to irreversible decomposition and a buildup neutral Ir(III)(dFCF3ppy)3-(5,5'-dCF3 bpy·-) [Ir(dCF3·-)]0) species. The rate PET reaction, krxn, between two oppositely charged ions was determined by monitoring growth absorption features associated with singly reduced product molecule, [Ir(dCF3·-)]0, various solvents range εr. reaction [Ir(dCF3) - BAr4F] predicted be nonspontaneous (ΔGPET ≥ 0) high εr such as acetonitrile, we observe krxn ≃ 0 under these circumstances. However, increases decreases. attribute this change spontaneity electrostatic work described Born (ΔGS) Coulomb (W) correction terms Gibbs free energy (ΔGPET). often-neglected corrections can utilized design novel surprising chemistry. Our facile preparation [Ir(dCF3·-)]0 one example general rule: ion-paired reactants result energetic products chemically store photon without binding them.

Язык: Английский

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Thianthrenium salts to arynes: base promoted C‐N bond construction

Advanced Synthesis & Catalysis, Год журнала: 2024, Номер unknown

Опубликована: Окт. 18, 2024

Abstract Amines are widely found in natural products, drugs and pesticides. We have proposed a base‐promoted method for synthesizing polysubstituted aromatic amines. The reaction does not necessitate the involvement of transition metals, provided that an equivalent base is employed. In this process, aryl thianthrenium salt serves as precursor to arynes, which subsequently distorted by induction effect different substituents. attack amine nucleophiles results formation series multi‐substituted products.

Язык: Английский

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Mechanosynthesis of ruthenium trisbipyridyl complexes and application in photoredox catalysis in a ball-mill

RSC Mechanochemistry, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 8, 2024

Ball-milling allowed the efficient preparation of ruthenium complexes with photoredox properties. With a transparent and chemically resistant milling jar in epoxy resin, photoreductive dehalogenation was realized efficiently solventless manner.

Язык: Английский

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Photoluminescent ruthenium(II) bipyridyl complexes containing phosphonium ylide ligands

Chemical Communications, Год журнала: 2024, Номер unknown

Опубликована: Янв. 1, 2024

An unprecedented photoluminescent phosphonium ylide Ru( ii ) bipyridyl complex was reported to be active in visible-light photocatalyzed single electron and energy transfer processes.

Язык: Английский

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