Is It Conjugated or Not? The Theoretical and Experimental Electron Density Map of Bonding in -CHCHCOCH-C≡C-C≡C--CHCOCHCH.

The electron density of -CHCHCOCH-C≡CC≡C--CHCOCHCH has been investigated on the basis of single-crystal X-ray diffraction data collected to high resolution at 100 K and from theoretical calculations. An analysis of the X-ray data of the diyne showed interesting "liquidity" of electron distribution along the carbon chain compared to 1,2-diphenylacetylene. These findings are compatible with the results of topological analysis of Electron Localization Function (ELF), which has also revealed a larger (than expected) concentration of the electron density at the single bonds.

Analysis of charge density in nonaaquagadolinium(III) trifluoromethanesulfonate - insight into Gd-OH bonding.

The experimental charge-density distribution in [Gd(HO)](CFSO) has been analysed and compared with the theoretical density functional theory calculations. Although the Gd-OH bonds are mainly ionic, a covalent contribution is detectable when inspecting both the topological parameters of these bonds and the natural bond orbital results. This contribution originates from small electron transfer from the lone pairs of oxygen atoms to empty 5d and 6s spin orbitals of Gd.

Advances and Property Investigations of an Organic-Inorganic Ferroelectric: (diisopropylammonium)[CdBr].

The preparation of materials featuring more than one ferroelectric phase represents a promising strategy for controlling electrical properties arising from spontaneous polarization, since it offers an added advantage of temperature-dependent toggling between two different ferroelectric states. Here, we report on the discovery of a unique ferroelectric-ferroelectric transition in diisopropylammonium tetrabromocadmate (, (CHN)[CdBr]) with a value of 244 K, which is continuous in nature. Both phases crystallize in the same polar orthorhombic space group, 2.

Symmetry breaking structural phase transitions, dielectric properties and molecular motions of formamidinium cations in 1D and 2D hybrid compounds: (NHCHNH)[BiCl] and (NHCHNH)[BiBr].

Two organic-inorganic hybrid halobismuthates(iii), (NH2CHNH2)3[Bi2Cl9] (FBC) and (NH2CHNH2)3[Bi2Br9] (FBB), have been prepared with their structures revealed by single-crystal X-ray diffraction at various temperatures. FBC is characterized by one-dimensional (1D) [Bi2Cl9]3-∞ anionic chains built by edge-sharing BiCl6 octahedra, whereas FBB adopts a layer structure (2D) [Bi2Br9]3-∞. Both materials were found to exhibit a rich polymorphism in the solid state.