Shared posts

25 Jul 06:58

From Particle-in-a-Box Thought Experiment to a Complete Quantum Theory?

by Jixin, Chen
The Schrödinger equation provides wavefunctions that describe the behavior of atoms, molecules, and materials, but constructing these wavefunctions by basis sets from fitting experimental data has rendered quantum chemistry predominantly empirical. The computational intensity of this process arises partly from the requirement to integrate wavefunctions across space to calculate energy levels. In this manuscript, a novel equation is proposed that significantly accelerates the computation of energy levels compared to classical quantum mechanics. Leveraging the first law of thermodynamics, which dictates that an equilibrium system maintains its total energy, an energy density function is derived that exhibits spatial uniformity and eliminates the need for normalization and renormalization. Consequently, the energy calculation no longer necessitates the integration of the entire wavefunction and transforms the second-order differential equation into a first-order counterpart. This new equation draws inspiration from the energy conservation method employed in solving classical mechanics problems like the pendulum. Remarkably, it successfully quantizes the energy levels of classical quantum systems, including the particle-in-a-box thought experiment, harmonic oscillator, and free spin, relying on simple rules such as momentum conservation. Therefore, it holds the potential to fit experimental data and reduce computational costs in modern quantum chemistry calculations.
23 Feb 16:29

Discovery of natural-product-derived sequanamycins as potent oral anti-tuberculosis agents

by Jidong Zhang, Christine Lair, Christine Roubert, Kwame Amaning, María Belén Barrio, Yannick Benedetti, Zhicheng Cui, Zhongliang Xing, Xiaojun Li, Scott G. Franzblau, Nicolas Baurin, Florence Bordon-Pallier, Cathy Cantalloube, Stephanie Sans, Sandra Silve, Isabelle Blanc, Laurent Fraisse, Alexey Rak, Lasse B. Jenner, Gulnara Yusupova, Marat Yusupov, Junjie Zhang, Takushi Kaneko, T.J. Yang, Nader Fotouhi, Eric Nuermberger, Sandeep Tyagi, Fabrice Betoudji, Anna Upton, James C. Sacchettini, Sophie Lagrange
Macrolides generally have low efficacy against tuberculosis, but a class of macrolides called “sequanamycins” overcomes the resistance of Mycobacterium tuberculosis to macrolides and can be optimized for potent activity against a variety of Mycobacterium tuberculosis strains, including drug-resistant ones.
10 Oct 06:22

Organothianthrenium salts: synthesis and utilization

Chem. Sci., 2022, 13,13690-13707
DOI: 10.1039/D2SC04507A, Review Article
Open Access Open Access
Huan Meng, Ming-Shang Liu, Wei Shu
This review summarizes the synthesis of diverse organothianthrenium salts from various precursors and their applications in organic synthesis to forge new C–C, C–H and C–heteroatom bonds by C–S bond cleavage with different mechanistic considerations.
The content of this RSS Feed (c) The Royal Society of Chemistry