Search Results - "Shaik, Sason"

How to Conceptualize Catalytic Cycles? The Energetic Span Model by Kozuch, Sebastian, Shaik, Sason

“…A computational study of a catalytic cycle generates state energies (the E-representation), whereas experiments lead to rate constants (the k-representation)…”
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Cytochrome P450The Wonderful Nanomachine Revealed through Dynamic Simulations of the Catalytic Cycle by Dubey, Kshatresh Dutta, Shaik, Sason

“…Conspectus This Account addresses the catalytic cycle of the enzyme cytochrome P450 (CYP450) as a prototypical biological machine with automatic features…”
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An anatomy of the two-state reactivity concept: Personal reminiscences in memoriam of Detlef Schröder by Shaik, Sason

“…Two-state reactivity (TSR) has become a widely used concept in bioinorganic and metallo-enzymatic chemistry. This concept was conceived in response to puzzling…”
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My Vision of Electric-Field-Aided Chemistry in 2050 by Shaik, Sason

“…This manuscript outlines my outlook on the development of electric-field (EF)-mediated-chemistry and the vision of its state by 2050. I discuss applications of…”
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Electric-Field Mediated Chemistry: Uncovering and Exploiting the Potential of (Oriented) Electric Fields to Exert Chemical Catalysis and Reaction Control by Shaik, Sason, Danovich, David, Joy, Jyothish, Wang, Zhanfeng, Stuyver, Thijs

“…This Perspective discusses oriented external-electric-fields (OEEF), and other electric-field types, as “smart reagents”, which enable in principle control…”
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Interplay of Tunneling, Two-State Reactivity, and Bell–Evans–Polanyi Effects in C–H Activation by Nonheme Fe(IV)O Oxidants by Mandal, Debasish, Shaik, Sason

“…The study of C–H bond activation reactions by nonheme FeIVO species with nine hydrocarbons shows that the kinetic isotope effect (KIE) involves strong…”
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Chemistry is about energy and its changes: A critique of bond-length/bond-strength correlations by Kaupp, Martin, Danovich, David, Shaik, Sason

“…•Bond-length/bond-strength correlations are in widespread use.•They are empirical rules but sometimes erroneously viewed as physical laws.•Many exceptions are…”
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Kinetic Isotope Effect Determination Probes the Spin of the Transition State, Its Stereochemistry, and Its Ligand Sphere in Hydrogen Abstraction Reactions of Oxoiron(IV) Complexes by Mandal, Debasish, Mallick, Dibyendu, Shaik, Sason

“…Conspectus This Account outlines interplay of theory and experiment in the quest to identify the reactive-spin-state in chemical reactions that possess a few…”
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Na⋅⋅⋅B Bond in NaBH3−: Solving the Conundrum by Radenković, Slavko, Shaik, Sason S., Braïda, Benoît

“…Bonding in the recently synthesized NaBH3− cluster is investigated using the high level Valence Bond BOVB method. Contrary to earlier conclusions, the Na−B…”
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Kinetic-Quantum Chemical Model for Catalytic Cycles: The Haber−Bosch Process and the Effect of Reagent Concentration by Kozuch, Sebastian, Shaik, Sason

“…A combined kinetic-quantum chemical model is developed with the goal of estimating in a straightforward way the turnover frequency (TOF) of catalytic cycles,…”
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Promotion Energy Analysis Predicts Reaction Modes: Nucleophilic and Electrophilic Aromatic Substitution Reactions by Stuyver, Thijs, Shaik, Sason

“…To develop an approach to pre-emptively predict the existence of major reaction modes associated with a chemical system, based on exclusive consideration of…”
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Catalysis of Methyl Transfer Reactions by Oriented External Electric Fields: Are Gold–Thiolate Linkers Innocent? by Ramanan, Rajeev, Danovich, David, Mandal, Debasish, Shaik, Sason

“…Oriented external electric fields (OEEFs) are potent effectors of chemical change and control. We show that the Menshutkin reaction, between substituted…”
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Hydrogen-Abstraction Reactivity Patterns from A to Y: The Valence Bond Way by Lai, Wenzhen, Li, Chunsen, Chen, Hui, Shaik, Sason

“…“Give us insight, not numbers” was Coulson’s admonition to theoretical chemists. This Review shows that the valence bond (VB)‐model provides insights and some…”
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Exchange-enhanced reactivity in bond activation by metal–oxo enzymes and synthetic reagents by Shaik, Sason, Chen, Hui, Janardanan, Deepa

“…Principles based on overlaps and interactions between bonding and antibonding orbitals are known to control chemical reactivity. This Perspective discusses…”
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Molecular Dynamics and QM/MM Calculations Predict the Substrate-Induced Gating of Cytochrome P450 BM3 and the Regio- and Stereoselectivity of Fatty Acid Hydroxylation by Dubey, Kshatresh Dutta, Wang, Binju, Shaik, Sason

“…Theory predicts herein enzymatic activity from scratch. We show that molecular dynamics (MD) simulations and quantum-mechanical/molecular mechanics (QM/MM)…”
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Automatic analysis of computed catalytic cycles by Uhe, Andreas, Kozuch, Sebastian, Shaik, Sason

“…The energetic span model allows the estimation of the turnover frequency (TOF) of a catalytic reaction from its calculated energy profile. Furthermore, by…”
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Conformational Motion of Ferredoxin Enables Efficient Electron Transfer to Heme in the Full-Length P450TT by Wang, Zhanfeng, Shaik, Sason, Wang, Binju

“…Cytochrome P450 monooxygenases (P450s) are versatile biocatalysts used in natural products biosynthesis, xenobiotic metabolisms, and biotechnologies. In P450s,…”
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A Theory for Bioinorganic Chemical Reactivity of Oxometal Complexes and Analogous Oxidants: The Exchange and Orbital-Selection Rules by Usharani, Dandamudi, Janardanan, Deepa, Li, Chunsen, Shaik, Sason

“…Over the past decades metalloenzymes and their synthetic models have emerged as an area of increasing research interest. The metalloenzymes and their synthetic…”
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The roles of charge transfer and polarization in non-covalent interactions: a perspective from ab initio valence bond methods by Mo, Yirong, Danovich, David, Shaik, Sason

“…Noncovalent interactions are ubiquitous and have been well recognized in chemistry, biology and material science. Yet, there are still recurring controversies…”
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Two-State Reactivity in Low-Valent Iron-Mediated C–H Activation and the Implications for Other First-Row Transition Metals by Sun, Yihua, Tang, Hao, Chen, Kejuan, Hu, Lianrui, Yao, Jiannian, Shaik, Sason, Chen, Hui

“…C–H bond activation/functionalization promoted by low-valent iron complexes has recently emerged as a promising approach for the utilization of earth-abundant…”
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