in the recent work, the reaction mechanism between triphenylphosphine 1, dialkyl acetylenedicarboxylates 2 in the presence of nh-acid, such as 5-aminoindazole 3 were investigated theoretically. quantum mechanical studies were performed for evaluation of potential energy surfaces of all structures participated in the reaction mechanism both in gas phase and in dichloromethane. the first step of ...

Solvents can significantly alter the rates and selectivity of liquid-phase organic reactions, often hindering the development of new synthetic routes or, if chosen wisely, facilitating routes by improving rates and selectivities. To address this challenge, a systematic methodology is proposed that quickly identifies improved reaction solvents by combining quantum mechanical computations of the ...

Multi-scale computer simulations combine the computationally efficient classical algorithms with more expensive but also more accurate ab-initio quantum mechanical algorithms. This work describes one implementation of multi-scale computations using the Atomistic Simulation Environment (ASE). This implementation can mix classical codes like LAMMPS and the Density Functional Theory-based GPAW. An...

We combine techniques from quantum and from classical density functional theory (DFT) to describe electron–ion mixtures. For homogeneous systems, we show how to calculate ion–ion and ion–electron correlation functions within Chihara’s quantum hypernetted chain approximation, which we derive within a DFT formulation. We also sketch out how to apply the DFT formulation to inhomogeneous electron–i...

Portable embedded system applications involving image, video or speech processing regularly perform linear computations. Linear computations (e.g. discrete cosine transform (DCT), discrete Fourier transforms (DFT) and filtering operations) are often implemented in custom hardware to meet the constraints on performance and power consumption. These linear computations consist of a number of multi...

In this work, we present a method to build first order reduced density matrix (1-RDM) of molecule from variational Quantum Monte Carlo (VMC) computations by means given correlated mapping wave function. Such function is modeled on Generalized Valence Bond plus Complete Active Space Self Configuration Interaction form and fits at best the resulting Slater-Jastrow VMC. The accuracy proposed has b...