Quantum chemical calculations of the structures and thermodynamics of homolytic dissociation of the central P-P and N-N bonds in tetrakis(disyl)diphosphine and tetrakis(di-tert-butylsilyl)hydrazine have been performed. The theory predicted negative standard enthalpies for homolytic bond dissociation in both cases, -71.0 and -108.4 kJ mol(-1) for the diphosphine and hydrazine, respectively, usin...

For large reactive systems, the calculation of energies can be simplified by treating the active part with a high-level quantum mechanical ~QM! ~ab initio or density functional! approach and the environment with a less sophisticated semiempirical ~SE! approach, as an improvement over the widely used hybrid quantum mechanical/molecular mechanical ~QM/MM! methods. An example is the interaction be...

Large scale Density Functional Theory (DFT) based electronic structure calculations are highly time consuming and scale poorly with system size. While semi-empirical approximations to DFT result in a reduction in computational time versus ab initio DFT, creating such approximations involves significant manual intervention and is highly inefficient for high-throughput electronic structure screen...

The DFT and Test challenges faced, and the solutions applied, to the ARMl026EJ microprocessor core are described in this paper. New DFT techniques have been created to address the challenges of distributing a DFT core solution that will ultimately end up in many different environments. This core was instantiated into a test chip. The new DFT features were utilized successfully in the SOC.

Zinc proteases are ubiquitous and the zinc ion plays a central function in the catalytic mechanism of these enzymes. A novel class of mechanism-based inhibitors takes advantage of the zinc ion chemistry in carboxypeptidase A (CPA) to promote covalent attachment of an inhibitor to the carboxylate of Glu-270, resulting in irreversible inhibition of the enzyme. The effect of the active site zinc i...

The DFT and Test challenges faced, and the solutions applied, to the ARM1026EJ microprocessor core are described in this paper. New DFT techniques have been created to address the challenges of distributing a DFT core solution that will ultimately end up in many different environments. This core was instantiated into a test chip. The new DFT features were utilized successfully in the SoC.

Orbital-free density-functional theory (OF-DFT) with modern kinetic-energy density functionals (KEDFs) is a linear scaling technique that accurately describes nearly-free-electron-like (main group) metals. In an attempt towards extending OF-DFT to transition metals, here we consider whether OF-DFT can be used effectively to study Ag, a metal with a localized d shell. OF-DFT has two approximatio...

well-defined crystalline pbse nanocubes and nanospheres have been synthesized through a simple hydrothermal method by using pb2+- edta and pb2+- oleylamine complexes at 180°c for different reaction times. composition and morphology of the samples have been characterized by means of xrd and sem. gradual release process of pb2+ from pb2+-edta and pb2+-oleylamine complexes can adjust the growth ra...

We present an extension of reverse engineered Kohn-Sham potentials from a density matrix renormalization group calculation towards the construction functional theory via deep learning. Instead applying machine learning to energy itself, we apply these techniques potentials. To this end develop scheme train neural network represent mapping local densities Finally, use up-scale simulation larger ...

In this article, we investigate the linear precoder based on the maximization of the minimum Euclidean distance between two received data vectors. This new precoding matrix is expressed as the product of a power allocation matrix and an input-shaping matrix. The input-shaping matrix is selected as a normalized discrete Fourier transform-matrix, and the optimal power allocation depends on the ch...