The X-ray charge density analysis of a hydroxynaphthoquinnne derivative was obtained by multipolar Hansen-Coppens formalism refinement through high resolution X-ray diffraction data at 100(1) K. The molecularproperties of the title compound resulted from the combined experimental and the quantum theory of atoms inmolecules (QTAIM) studies. The topological properties of the covalent bonds and of...

Halogen bonds (X-bonds) are shown to be geometrically perpendicular to and energetically independent of hydrogen bonds (H-bonds) that share a common carbonyl oxygen acceptor. This orthogonal relationship is accommodated by the in-plane and out-of-plane electronegative potentials of the oxygen, which are differentially populated by H- and X-bonds. Furthermore, the local conformation of a peptide...

Heating K(4)Mo(2)Cl(8) and 2 equiv of Li[RC(NDipp)(2)] (R = H, Ph; Dipp = 2,6-i-Pr(2)C(6)H(3)) in tetrahydrofuran (THF) at 60 degrees C gives two paddlewheel type quadruply bonded dimolybdenum complexes, Mo(2)(mu-Cl)[Cl(2)Li(OEt(2))][mu-eta(2)-RC(N-2,6-i-Pr(2)C(6)H(3))(2)](2) (R = H (1), Ph (2)). The Mo-Mo bond lengths of 1 and 2 are 2.0875(4) and 2.0756(8) A, respectively, indicating typical M...

This paper characterizes conditions under which a risky coupon bond is equivalent to a portfolio of risky zero-coupon bonds. This characterization is extended to enable the estimation of firm specific zero-coupon bond prices from risky coupon bond prices for the determination of firm specific credit risk curves.  2004 Elsevier Inc. All rights reserved.

in the present work, an extensive theoretical calculation study on histidine-histidine dipeptide in gas phase is done by using dft method with gaussian 98 program. through investigations on the molecular geometries of this molecule it is found that there is six rings in the molecules not two rings. the presence of four intramolecular hydrogen bonds is responsible for the formation of additional...