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Abstract Two series of biological based (nano) gelatoric ionic liquids (NGILs) were synthesized in high yield (96–98%). All the new NGILs were characterized by 1H NMR, 13C NMR, FT-IR, XRD, SEM, and TGA/DTA. Their ability to act as catalysts in the synthesis of 5‑amino‑3‑(3‑nitrophenyl)‑1‑phenyl‑1 H ‑pyrazole‑4‑carbonitrile via vinylogous anomeric based oxidation was examined. They were reused at least two times with a marginal decreasing their activity. Graphical abstract A range of biological based nano-gelatoric ionic liquids (NGILs) were synthesized and their structures fully characterized. There were used as catalysts in the synthesis pyrazole via anomeric based oxidation. Unlabelled Image Highlights • Two classes of biological based biological based nano-gelatoric ionic liquids (NGILs) were synthesized. • NGILs possess unique features such as high adhesive, high stretch as well as mechanical flexibility. • Target molecule was synthesized via vinylogous anomeric based oxidation in the presence of NGILs as efficient catalysts. [ABSTRACT FROM AUTHOR]

Glasses of the composition 24 M 2 SO 4 -1 M 2 O-52 ZnO-23 P 2 O 5 with M Li, Na, K, Rb, Cs, and Ag were prepared by conventional melt-quenching. Variation of the monovalent cation results in distinct changes in the thermo-physical, mechanical, and chemical properties. From Li to Cs, the calorimetric glass transition temperature and the stability against crystallization increase significantly. This trend is contrary to expectations in covalent glasses, but consistent with the behavior of ionic fluoride glasses. However, chemical and mechanical properties are consistent with the trend observed for covalent glasses as hardness and elastic modulus are drastically lowered from Li to Cs glasses. Modifier substitution with the heavier Ag ion has often similar effects as lithium substitution due to their comparably small coordination number (i.e., four) in the studied glasses. Raman- and IR-spectroscopic studies were carried out in order to correlate the variations in the glass properties with variations of the glass structure. Here, sulfate anions show preferential bonding to the monovalent cations while phosphate groups are preferentially linked to zinc-cations. For larger alkali cations the tetrahedral phosphate and sulfate groups show a reduction of symmetry, i.e., deviations from tetrahedral symmetry when acting as bi- or multi-dentate ligands. [ABSTRACT FROM AUTHOR]

In this paper, we report the study of sub-T g dynamics of chlorpromazine hydrochloride. The substance is another pharmaceutical and glass-forming protic ionic conductor investigated by our group. We describe both ionic and dipolar behaviors and show the way in how to tell them apart. Mainly, we focus on the dynamics of the slower of the two secondary relaxation processes found. By means of the dielectric spectroscopy we study its behavior as a function of temperature and pressure. Moreover, on the basis of quantum-mechanical calculations, we designate the mechanism for faster secondary relaxation as the conformational change of the dimethylamine group. Finally, we compare the findings with data of lidocaine hydrochloride, procaine hydrochloride and procainamide hydrochloride to answer the question of which features are typical for the protic ionic glasses and which are associated with specific chemical structure. [ABSTRACT FROM AUTHOR]

The electrical transport during the crystallization of ternary Li2SO4-Li2O-P2O5 glassy ionic system reveals interesting results. Electrical conductivity isotherms recorded at the crystallization temperature are found to be of immense importance, especially, in the understanding of phase transformation. The electrical conductivity falls rapidly during crystallization of LiPO3 compound and saturates at its completion. Such studies on conductivity isotherms further confirm the suppression of crystallization with addition of Li2SO4 in the glass matrix. A systematic variation of the Cole-Cole plots and conductivity spectra during crystallization further suggests a slow and predetermined process of glass-ceramic formation. The mechanism of electrical transport during crystallization is also explained using a crystallite bypass model. It is further revealed that the samples remain purely ionic during and after crystallization. [ABSTRACT FROM AUTHOR]

Silver iodide-silver molybdate glasses, (AgI)x(Ag2MoO4)1 - x, with x = 0.75 and x = 0.67, exhibit high ionic conductivity, comparable to that of some ionic liquids at room temperature, and low values of the calorimetric glass transition temperature. The behaviour of the attenuation of acoustic waves as a function of temperature in silver iodomolybdate glasses below Tg is peculiar, arising from two different and almost overlapping relaxational contributions. In this work we investigate the frequency dependent conductivity and the dielectric properties of silver iodide-silver molybdate glasses in the mHz-GHz frequency range at temperatures between 300 K and 70 K, aiming in particular to ascertain whether a correlation can be found between the features of the dielectric response and the anomalous mechanical response of these fast ion conducting glasses. [ABSTRACT FROM AUTHOR]

The thermal expansion of the ionically conducting silver iodide-silver molybdate glass (AgI)0.67(Ag2MoO4)0.33 was investigated from low temperatures up to about the glass transition region using a capacitance dilatometer via a quasi-adiabatic method. The results do not show any anomalous behaviour in a temperature range where the existence of relaxation processes with peculiar features was previously revealed using mechanical spectroscopy, but rather a monotonic increase of positive values of the thermal expansion coefficient. [ABSTRACT FROM AUTHOR]

We evaluate the stability of various structures for a Ca 2 (NO 3 ) 7 core unit compensated by K or Rb ions, as a basic constituent of the glass-forming melts of CKN and CRbN compounds [3ANO 3   ·  2Ca(NO 3 ) 2 with A  =  K or Rb]. We find that three alternative structures are stable for the core unit and lie at approximately the same energy, provided the Ca-NO 3 overlap repulsion is stiff enough as suggested by the planar structure of the NO 3 group, but independent of the amount of electronic charge transfer to these groups. In these structures, each Ca ion can lie in a fourfold or a fivefold coordination by NO 3 groups, so that the two Ca ions can be bridged by one, two, or three NO 3 groups. This picture is compatible with the accepted view of CKN as a prototype fragile glass-former and with the stability of mixed-nitrate glasses over a broad range of composition. [ABSTRACT FROM AUTHOR]

Abstract: Activation enthalpies of ionic conductivities in Na–Rb alumino-germanate and borate glasses are reviewed. Correlations between the activation enthalpy and the ratio of average distances between like alkali ions, 〈d ion〉, to the average distances between network–former atoms, 〈d network〉, are elucidated for single- and mixed-alkali glasses. The Haven ratio is shown to decrease with decreasing 〈d ion〉/〈d network〉. Interstitial-like and substitutional-like subnetworks of ion sites are suggested. The experimentally observed dependence of the Haven ratio on 〈d ion〉/〈d network〉 is consistently reproduced by a Monte Carlo simulation of ion dynamics on this random network including single and collective ion jumps. [Copyright &y& Elsevier]