in this paper, the hydrogen bonding (hb) effects on the nmr chemical shifts of selected atoms in serineand serine-nh2o complexes (from one to ten water molecules) have been investigated with quantummechanical calculations of the 15n and 13c tensors. interaction with water molecules causes importantchanges in geometry and electronic structure of serine.for the compound studied, the most importan...

topological indices are the numerical value associated with chemical constitution purporting for correlation ofchemical structure with various physical properties, chemical reactivity or biological activity. graph theory is adelightful playground for the exploration of proof techniques in discrete mathematics and its results haveapplications in many areas of sciences. one of the useful indices ...

topological indices are one of the oldest and most widely used descriptors in quantitative structureproperties relationvhips (qspr). amongst the topological indices used a,s descriptors in qspic., the wienerindex is by far the most popular index. as it has been shown that the wiener index has a strong correlationwith the chemical propenies of the compound.in this study, the relationship between...

Ab initio calculations are performed for the X̃2E′′ 1 and à 2A′′ 2 states of the cyclopentadienyl radical. An important goal of these calculations is to guide the analysis of the experimentally observed Ã2A′′ 2 -X̃ 2E′′ 1 electronic spectrum. Vibrational frequencies for both the X̃ and à state are reported. Large changes

Contact maps have been used in ab initio methods for the problem of protein structure prediction problem. Secondary structures and contacts made by the residues are clearly visible in the contact maps where helices are seen as thick bands and the beta sheets are seen as orthogonal to the diagonal. This paper explores the idea of extracting rules from contact maps to represent “protein fold” inf...

I discuss the spectrum of hadrons containing heavy quarks (b or c), and how well the experimental results are matched by theoretical ideas. Useful insights come from potential models and applications of Heavy Quark Symmetry and these can be compared with new numerical results from the ab initio methods of Lattice QCD.

The need to determine phases is a major bottleneck in a fully automated X-ray crystallography pipeline. The problem commonly called phasing can be solved by a computational method called molecular replacement (MR). With the deposition of more and more proteins into the Protein Data Bank (PDB), it has been shown that the MR yields better initial models. In this paper, ab initio first model gener...

The recent discovery of pure boron nanotubes raises questions about their detailed atomic structure. Previous simulations predicted tubular structures with smooth or puckered surfaces. Here, we present some novel results based on ab initio simulations of bundled single–wall zigzag boron nanotubes (ropes). Besides the known smooth and puckered modifications, we found new forms that are radially ...

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