X-ray diffraction studies on homologous thallium soaps below the temperature range of the neat phase 1. Calculation and comparison of the structure parameters of unit cells

Thermal and Structural Study of the Crystal Phases and Mesophases in the Lithium and Thallium(I) Propanoates and Pentanoates Binary Systems: Formation of Mixed Salts and Stabilization of the Ionic Liquid Crystal Phase

“…From these results, it is clear to infer the more packed arrangement in the cases of the lithium and mixed alkanoates than for the thallium salts. The structure of the thallium(I) alkanoates was studied previously by Dorfler et al, , giving values of around 24 Å 2 for S , for longer members of the series, comparable with the one found in this work for the TlC3. This great value of S (and S ′) explains the presence of disorder in the chains of the thallium(I) alkanoates at room temperature, observed by FTIR, forming the so-called “condis” phase (solid phase where the alkyl chains are conformationally disordered), already studied. , It also fits perfectly with the difficulty in obtaining good results in the X-ray study (in single crystal and in powder) of the ionic layer structure in the compounds of the TlC n series when n ≥ 4: the single-crystalline flakes were found to be “plastic”, and easily bendable.…”

“…Thallium(I) and lithium alkanoates (TlC n and LiC n ) have been widely studied in the past decades by several techniques, such as adiabatic calorimetry, − DSC, − DTA, , XRD, , and others . However, many aspects about the thermal behavior, the crystal phase structures, and their mesophases are still not explained.…”

Structure and Mesomorphism of Silver Alkanoates

“…Silver behenate and the other silver alkanoates do not simply melt in one step upon heating, but they undergo a series of phase transitions before they melt with thermal decomposition. − Although some of these transitions are crystal-to-crystal transitions, most of them are mesophase transitions. The thermal behavior of the silver alkanoates is much more complex than the thermal behavior of the other transition-metal alkanoates or of the lanthanide(III) alkanoates , and is more reminiscent to that of the alkanoates of the alkali and earth-alkaline metals , or of thallium(I). − Whereas the thermal behavior of the alkali and earth-alkaline metals has been studied in depth, much less is known about the nature of the phase transitions in the silver alkanoates. − The most detailed study of the thermal properties so far, is the work of Bokhonov et al . These authors have studied the thermal behavior of silver laurate, myristate, palmitate, and stearate by DSC, polarizing optical microscopy, and in-situ high-temperature small-angle X-ray scattering.…”