Natalia V. Avramenko

TERNARY SYSTEM OF C60 AND C70 WITH 1,2-DIMETHYLBENZENE

Differential scanning calorimetry, X-ray, and solubility measurements were used to study phase equilibria in the ternary system C60-C70-1,2-dimethylbenzene up to the boiling point of the solvent. Formation of the two ternary phases was confirmed. Partial solubilities of C60 and C70 were measured and calculated.

Thermal behaviour of the crystals formed in the buckminsterfullerene-toluene, o-xylene and bromobenzene systems

Abstract Unusual solubility versus temperature dependence for C 60 fullerene in toluene and several other solvents is due to the formation of solid solvates. Temperature Maximum of Solubility (TMS) in toluene coincides with the incongruent melting point of the solvate with the mole ratio of C 60 to toluene 1:1.8 ± 0.5. Similar results were obtained in the system C 60 -bromobenzene, C 60 -o-xylene, where solvates with the mole ratio 1:2 were found. Stoichiometry of the solvates of C 60 with the aromatic solvents are discussed in terms of incongruent melting.

Thermochemistry of Solvated Crystals of C60> and C70> with o-Xylene

Differential scanning calorimetry (DSC) was used to study the binary systems of C60-o-xylene and C70-o-xylene and the ternary system C60-C70-o-xylene. Fullerene C60 formed solvated crystals C60·2C8H10 with incongruent melting point 320 K and with enthalpy of decomposition 31±3 kJ (mol of C60)-1. Two solvated crystals of C70 with incongruent melting points 283 and 369 K, and with decomposition enthalpies 18.5±2.2 and 23.0±1.5 kJ (mol of C70)-1, were formed from o-xylene solutions. Three ternary compositions with C60/C70 mole ratios of 3:1, 1:1 and 1:3 were scanned by DSC.

INTERPOLYMER COMPLEXES OF A NEW TYPE Three-component interpolymer complexes involving a monobasic low molar mass mediator

A new type of three-component interpolymer complexes (3IPCM) formed by two similarly charged polyelectrolytes and an oppositely charged low molar mass compound was studied by DSC, NMR and X-ray methods. The low molar mass monobasic compounds in these complexes act as mediators. This type of complexes differs from earlier-obtained 3IPCM, which contained a dibasic low molar mass mediator.The present 3IPCM were obtained from two polymers (polyacrylic acid and sodium polyphosphate) and bases such as 4-vinylpyridine and 2-methyl-5-vinylpyridine.

Application of DSC for the determination of purity of organic semiconductors

DSC method was developed for the analysis of organic and inorganic substances. Beside the “common” method “short” method is applied. Comparison of these two methods for the determination of purity on standard samples like indium, benzil, caffeine showed good similarity of the results so it allowed to use a “short” method for the determination of the amount of impurity in semiconductors such as bis(ethylenedithio)tetrathiofulvalen and tetrathiotetracene. These compounds are unstable and begin to decompose some times during melting.ZusammenfassungFür die Analyse von organischen und anorganischen Substanzen wurde ein DSC-Verfahren entwickelt. Neben dem “herkömmlichen” wurde auch ein “Kurzverfahren” angewendet. Der Vergleich der Ergebnisse der zwei Verfahren bei der Reinheitsbestimmung von Standardproben, wie z.B. Indium, Biphenyl und Koffein zeigte eine gute übereinstimmung. Das Kurzverfahren kann somit gut zur Bestimmung des Verunreinigungsgrades von Halbleitern wie z.B. Bis-(äthylendithio)-tetrathiofulvalen und Tetrathiotetrazen genutzt werden. Diese Verbindungen zeigen nämlich während des Schmelzens mitunter Zersetzungserscheinungen.РЕжУМЕМЕтОД Дск Был РАжРАБО тАН Дль АНАлИжА ОРгАНИЧЕскИх И НЕОРг АНИЧЕскИх ВЕЩЕстВ. кРОМЕ “ОБЩЕгО МЕтОДА ”, Был ИспОльжОВАН И “к ОРОткИИ” МЕтОД. сОпОстАВлЕНИЕ ЁтИх ДВУх МЕтОДОВ Дль ОпРЕДЕлЕНИь ЧИст Оты тАкИх стАНДАРтНы х ОБРАжцОВ, кАк ИНДИИ, БИФЕНИл И кО ФФЕИН, пОкАжАл хОРОшЕЕ сОВпАДЕНИЕ Р ЕжУльтАтОВ, ЧтО пОжВО лИлО ИспОльжОВАть “кОРОт кИИ” МЕтОД Дль кОлИЧЕ стВЕННОгО ОпРЕДЕлЕНИь пРИМЕсЕ И В тАкИх ОРгАНИЧЕскИ х пОлУпРОВОДНИкАх, кАк БИс/ЁтИлЕНДИтИО/тЕтР АтИОФУльВАлЕН БИс/ЁтИлЕНДИтИО/тЕтР АтИОФУльВАлЕН И тЕтРАтИОтЕтРАцЕН. Ё тИ сОЕДИНЕНИь НЕУстО ИЧИВы И В НЕкОтОРОИ стЕпЕНИ НАЧИНАУт РАжлАгАтьс ь пРИ плАВлЕНИИ.

Solid Solvates of C60 Compositions and Thermodynamics

Compositions of the solid solvates of C60 with 1,2-dichlorobenzene and 1,3,5-trimethylbenzene were determined with the help of experimental procedures developed. Possible correlations between compositions and thermodynamic properties were discussed.