Ionic liquids (IL) and hydrogen bonding (H-bonding) are two diverse fields for which there is a developing recognition of significant overlap. Doubly ionic H-bonds occur when a H-bond forms between a cation and anion, and are a key feature of ILs. Doubly ionic H-bonds represent a wide area of H-bonding which has yet to be fully recognised, characterised or explored. H-bonds in ILs (both protic ...

Absorption spectra for 2,3-diaryl-2,3-diazabicyclo[2.2.2]octane radical cations (2(X)(*+)) and for their monoaryl analogues 2-tert-butyl-3-aryl-2,3-diazabicyclo[2.2.2]octane radical cations (1(X)(*+)) having para chloro, bromo, iodo, cyano, phenyl, and nitro substituents are reported and compared with those for the previously reported 1- and 2(H)(*+) and 1- and 2(OMe)(*+). The calculated geomet...

We have analyzed structure, stability, and Ru-NO bonding of the trans-[RuCl(NO)(NH3)4]2+ complex by using relativistic density functional theory. First, we focus on the bond dissociation energies associated with the three canonical dissociation modes leading to [RuCl(NH3)4]++NO+, [RuCl(NH3)4]2++NO, and [RuCl(NH3)4]3++NO-. The main objective is to understand the Ru-NO+ bonding mechanism in the c...

Orbital reconstructions and covalent bonding must be considered as important factors in the rational design of oxide heterostructures with engineered physical properties. We have investigated the interface between high-temperature superconducting (Y,Ca)Ba(2)Cu3O7 and metallic La(0.67)Ca(0.33)MnO3 by resonant x-ray spectroscopy. A charge of about -0.2 electron is transferred from Mn to Cu ions a...

INTRODUCTION The idea of Möbius aromaticity was first proposed by Heilbronner in 1964. He postulated that a molecule could gain Möbius aromatic stabilization if the nuclear framework were twisted so the porbitals composing the π-system would contain an odd number of nodes. To introduce a node in the orbitals, Heilbronner theorized that a series of p-orbitals could itself be twisted by contortin...

The molecular orbitals of 1, 1′-biphenyl-4,4′-dimethyldithiol (HS– CH2–C6H4–C6H4–CH2–SH) are identified from combined photoemission and inverse photoemission studies and compared with theory for several different surfaces, molecular conformations and molecular orientations. The preferential molecular orientations of biphenyldimethyldithiol, on both Au(111) and polycrystalline Co, are identified...

When Ni2+ is surrounded by a ligand field due to cyanide ligands, a square planar geometry results. However, when Ni2+ forms a complex with chloride a tetrahedral geometry results. To determine the cause of this difference, hybrization, bonding, the molecular orbital picture, and symmetry will be considered using several techniques. Because the spacings between energy levels depend on factors s...

When two electrons occupy the same bond at the same time, they repel each other, and their motions are not perfectly independent. We consider two approaches: molecular orbital theory, which assumes electrons do not repel each other and move independently, and valence bond theory, which assumes electrons interact so strongly they cannot be on the same nuclei at the same time. The truth lies betw...

The intermetallic compound Na49Cd58.5Sn37.5 was obtained in nearly 100% yield after fusion of the elements in stoichiometric proportions in a Nb container and quenching of the mixture. The structure was determined by single-crystal X-ray diffraction (rhombohedral, R3hm, Z ) 3, a ) 16.034(1) Å, c ) 50.64(1) Å; R, Rw(F) ) 3.3%, 4.2%). The covalently-bonded part of the structure is a network of ca...

In a typical solitonic distribution, the soliton density is distributed over the entire moleculeand the present work shows how its density can be decomposed into solitonic and antisolitoniccomponents. It is found that there exists a unique electron as soliton over the anionicnanoconductor, while there are many other solitons and antisolitons. The solitonic states are furtherdecomposed to the ca...