The parallel performance of the NWChem version 1.2 parallel direct-SCF code has been characterized on ve massively parallel supercomputers (IBM SP, Kendall Square KSR-2, Cray T3D and T3E, and Intel Touchstone Delta) using single-point energy calculations on seven molecules of varying size (up to 389 atoms) and composition ((rst-row atoms, halogens, and transition metals). We compare the perform...

Organic medicinal agents are compounds (molecules) composed of individual atoms linked via chemical bonds. The primary elements of OMAs are carbon (C) and hydrogen (H). Other elements found in lesser abundance in OMA structures include nitrogen (N), oxygen (O), sulfur (S), phosphorous (P) and halogens (F, Cl, Br, I). Examples of the contributions of these atoms in various drug molecules are sho...

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The title compound, C10H4I2O3, is an iodinated 3-formyl-chromone derivative, and the atoms are essentially coplanar [r.m.s. deviation = 0.049 Å, largest deviation from the least-squares plane = 0.111 (9) Å for the CH(=O) C atom]. In the crystal, mol-ecules are linked into a three-dimensional network through halogen bonds [I⋯O = 3.352 (5) and 3.405 (7) Å, C-I⋯O = 144.2 (3) and 154.5 (3)°, and C=...

The halogen bond in the thiirane···ClF complex is shown to be unusually strong using high-accuracy ab initio methods. Investigating the underlying mechanism of the interaction reveals a significant increase in charge transfer and suggests it should be labelled as a Mulliken inner complex.

The facile synthesis of the cage molecule (C110H56Br2) via a remarkable three-fold homo-coupling macrocyclization reaction using continuous flow methodology is reported. Synthesis via continuous flow chemistry improves the residence time, safety, and environmental profile of this synthetically challenging reaction. Further, the new cage possesses halogen atoms at its apex that serve to expand t...

In this study, on the combination of chlorpromazine with two aromatic rings, halogens are attached to the rings, and changes in the angles and lengths of the ipsos are calculated. Calculations show that by changing the halogen based on the amount of electronegativity, the magnitude and variation of the angular lengths The lengths of the links also change in the following order. The angles of th...