There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

Hexakis(dimethyl sulfoxide)scandium(III) iodide, [Sc(OS(CH(3))(2))(6)]I(3) contains centrosymmetric hexasolvated scandium(III) ions with an Sc-O bond distance of 2.069(3) angstroms. EXAFS spectra yield a mean Sc-O bond distance of 2.09(1) angstroms for solvated scandium(III) ions in dimethyl sulfoxide solution, consistent with six-coordination. Raman and infrared absorption spectra have been recorded, also of the deuterated compound, and analysed by means of normal coordinate methods, together with spectra of dimethyl sulfoxide. The effects on the vibrational spectra of the weak intermolecular C-H...O interactions and of the dipole-dipole interactions in liquid dimethyl sulfoxide have been evaluated, in particular for the S-O stretching mode. The strong Raman band at 1043.6 cm(-1) and the intense IR absorption at 1062.6 cm(-1) have been assigned as the S-O stretching frequencies of the dominating species in liquid dimethyl sulfoxide, evaluated as centrosymmetric dimers with antiparallel polar S-O groups. The shifts of vibrational frequencies and force constants for coordinated dimethyl sulfoxide ligands in hexasolvated trivalent metal ion complexes are discussed. Hexasolvated scandium(iii) ions are found in dimethyl sulfoxide solution and in [Sc(OSMe(2))(6)]I(3). The iodide ion-dipole attraction shifts the methyl group C-H stretching frequency for (S-)C-H...I(-) more than for the intermolecular (S-)C-H...O interactions in liquid dimethyl sulfoxide.

Vibrational spectroscopic force field studies of dimethyl sulfoxide and hexakis (dimethyl sulfoxide) scandium(III) iodide, and crystal and solution structure of the hexakis (dimethyl sulfoxide (scandium)(III) ion

Conductivity and foldability enhancement of Ag patterns formed by PVAc modified Ag complex inks with low-temperature and rapid sintering

The influence of low-molecular-weight poly(ethylene glycol) (PEG, Mw ≈ 550 Da) plasticizers on the rheology and ion-transport properties of fluorosulfonimide-based polyether ionic melt (IM) electrolytes has been investigated experimentally and via molecular dynamics (MD) simulations. Addition of PEG plasticizer to samples of IM electrolytes caused a decrease in electrolyte viscosity coupled to an increase in ionic conductivity. MD simulations revealed that addition of plasticizer increased self-diffusion coefficients for both cations and anions with the plasticizer being the fastest diffusing species. Application of a VTF model to fit variable-temperature conductivity and fluidity data shows that plasticization decreases the apparent activation energy (Eₐ) and pre-exponential factor A for ion transport and also for viscous flow. Increased ionic conductivity with plasticization is thought to reflect a combination of factors including lower viscosity and faster polyether chain segmental dynamics in the electrolyte, coupled with a change in the ion transport mechanism to favor ion solvation and transport by polyethers derived from the plasticizer. Current interrupt experiments with Li/electrolyte/Li cells revealed evidence for salt concentration polarization in electrolytes containing large amounts of plasticizer but not in electrolytes without added plasticizer.

The Effect of Low-Molecular-Weight Poly(ethylene glycol) (PEG) Plasticizers on the Transport Properties of Lithium Fluorosulfonimide Ionic Melt Electrolytes

The processes of molecular relaxation in the binary nitrate–perchlorate solid systems LiNO3–LiClO4, NaNO3–NaClO4, and KNO3–KClO4 have been investigated using Raman spectroscopy. It has been found that the relaxation time of the ν1(A) vibration of the NO3- anion in the binary solid system is shorter than that in the pure metal nitrates. It has been shown that an increase in the relaxation rate is caused by the existence of an additional mechanism of relaxation of vibrationally excited states of the nitrate ion in the system. This mechanism is associated with the excitation of a vibration of another anion (ClO4-), as well as with the “creation” of a lattice phonon. It has been established that the condition for the realization of the relaxation mechanism is that the difference between the frequencies of the aforementioned vibrations should correspond to the range of sufficiently high densities of states of the phonon spectrum.

Inelastic intermolecular exchange of vibrational quanta and relaxation of vibrationally excited states in binary solid systems

The processes of molecular relaxation in the solid NaNO3–NaNO2 and KNO3–KNO2 “nitrate–nitrite” binary systems have been investigated by Raman spectroscopy. The relaxation time of the vibration ν1(A) of an NO-
 3 anion in the binary system is found to be shorter than that in individual nitrate. The increase in the relaxation rate is explained by the existence of an additional mechanism of relaxation of vibrationally excited states of the nitrate ion in the system. This mechanism is related to the excitation of vibration of another anion (NO-
 2) and generation of a lattice phonon. It has been established that this relaxation mechanism is implemented provided that the difference between the frequencies of the aforementioned vibrations correspond to the range of sufficiently high density of states in the phonon spectrum.

Relaxation of vibrationally excited states in solid “nitrate–nitrite” binary systems

A Water-Soluble Ink Based on Diamine Silver(I) Carbonate, Ammonium Formate, and Polyols for Inkjet Printing of Conductive Patterns

The processes of molecular relaxation in solid binary carbonate-sulfate systems, such as Li2CO3-Li2SO4, Na2CO3-Na2SO4, K2CO3-K2SO4, have been studied by Raman spectroscopy. It has been revealed that the relaxation time of CO
 3
 2-
 anion vibration ν1(A) in a binary system is higher than in an individual carbonate. It is shown that an increase in the relaxation rate may be explained by the existence of an additional mechanism of the relaxation of vibrationally excited states of a carbonate anion. This mechanism is associated with the excitation of the vibration of another anion (SO
 4
 2-
 ) and the “birth” of a lattice phonon. It has been established that the condition for the implementation of such a relaxation mechanism is that the difference between the frequencies of these vibrations must correspond to the region of a rather high density of phonon spectrum states.

Relaxation of Vibrationally Excited States in Solid Binary Carbonate-Sulfate Systems

The structural and dynamic properties of lithium nitrate LiNO3 and its heterogeneous composites with a nanopowder of aluminum oxide Al2O3 at different temperatures, phase states, and concentrations of the Al2O3 nanopowder have been investigated using Raman scattering, differential thermal analysis, and X-ray diffraction. It has been shown that, in the (1–x)LiNO3 + xAl2O3 composites, an amorphous phase (for x ≥ 0.5) is formed, whose thermal effect is observed at 185°C. The calculations of the dynamic characteristics of vibrations of the nitrate ion, as well as the differential thermal and X-ray diffraction analyses, have demonstrated that the nanocomposite can be represented as a highly disordered “quasilattice” in which “sites” are occupied by nanoparticles with amorphous lithium nitrate shells and spaces between them (conventionally “interstitial sites”) become channels of a facilitated flow of the ion current.

A. M. Amirov

Papers

Inelastic intermolecular exchange of vibrational quanta and relaxation of vibrationally excited states in binary solid systems

Relaxation of vibrationally excited states in solid “nitrate–nitrite” binary systems

A Water-Soluble Ink Based on Diamine Silver(I) Carbonate, Ammonium Formate, and Polyols for Inkjet Printing of Conductive Patterns

Relaxation of Vibrationally Excited States in Solid Binary Carbonate-Sulfate Systems

Structural and dynamic properties of LiNO 3 + Al 2 O 3 nanocomposites