The present work reports the detailed B3LYP/6-311++G(d,p) study of most stable transand cisconfigurations photoisomerization in the core system of computational photochemistry-the 5,5'-disubstituted-1,1'-azobis (tetrazole) molecules. All computations were carried out in gas phase attemperature 293.15 K and pressure 1 atm. Firstly; the potential energy surface (PES) of the groundstate of the mol...

Abstract Calculations of point defect energetics with Density Functional Theory (DFT) can provide valuable insight into several optoelectronic, thermodynamic, and kinetic properties. These calculations commonly use methods ranging from semi-local functionals a-posteriori corrections to more computationally intensive hybrid functional approaches. For applications DFT-based high-throughput comput...

Electron density $\rho(\vec{r})$ is the fundamental variable in calculation of ground state energy with functional theory (DFT). Beyond total energy, features and changes distributions are often used to capture critical physicochemical phenomena materials. We present a machine learning framework for prediction $\rho(\vec{r})$. The model based on equivariant graph neural networks electron predic...

BACKGROUND The discrete Fourier transform (DFT) is often used as a spectral estimator for analysis of complex fractionated atrial electrograms (CFAE) acquired during atrial fibrillation (AF). However, time resolution can be unsatisfactory, as the frequency resolution is proportional to rate/time interval. In this study we compared the DFT to a new spectral estimator with improved time-frequency...

We describe extensions to the siesta density functional theory (dft) code [30], for the simulation of isolated molecules and their absorption spectra. The extensions allow for: • Use of a multigrid solver for the Poisson equation on a finite dft mesh. Non-periodic, Dirichlet boundary conditions are computed by expansion of the electric multipoles over spherical harmonics. • Truncation of a mole...

The discrete Fourier transform(DFT) has been widely applied in the field of signal processing. There are lots of architectures available in literature which are of computing N point DFT type. Such algorithms are called as FFT computation algorithms. However in some applications we need to computer the DFT for some of selected output bin indices only. One of such example is signal monitoring and...

FFT algorithms is one of the many methods used for the calculation of DFT, but they are preferred due to their increased speed and higher efficiency, which arises due to the fact that for the calculation of a N-point DFT, the sequence is broken into several segments and the DFT for each segment is calculated. However, for this many redundant memory spaces are required. The Butterfly structure f...

The Discrete Fourier Transform (DFT) is used to transform the samples in time domain into frequency domain coefficients. The Fast Fourier Transform (FFT) is a widely used algorithm that computes the Discrete Fourier Transform (DFT) using much less operations than a direct realization of the DFT. FFTs is of great significance to a wide variety of applications such as data compression, spectral a...

Since the invention of the mobile phone, a new generation of mobile communication standard has emerged every 10 years. Upgrading the technology of mobile networks in all areas takes few years. Hence, mobile phones should support the previous communication standards as well as the latest standards. Realizing a multi-standard mobile phone by multiple transceivers in parallel is neither a size-eff...

367 followed by addition which is completed in one clock unit time. The DFT is computed using a systolic cell described in [15]. For IBA-1 and IBA-2 the computation of the common connection polynomial is done by processing rows or columns serially. The computations of the connection polynomials for individual rows or columns in the case of Blahut's 2-D burst error correction are done concurrent...