Isomeric effects in structure formation and dielectric dynamics of different octanols

Abstract

The understanding of the microstructure of associated liquids promoted by hydrogen-bonding and constrained by steric hindrance is highly relevant in chemistry physics, biology and for many aspects of daily life....

X-ray scattering at beamline BL2 of DELTA: Studies of lysozyme-lysozyme interaction in heavy water and structure formation in 1-hexanol

“…This suggests a change in the kind of supramolecular arrangements, i.e. a trend from tighter and ring-like arrangements to larger, chain-like clusters as reported also for 1-octanol [26]. However, this change is not as significant as observed for 1-octanol which can be traced back to the smaller chain length and the related tendency to form smaller tighter clusters in general due to lesser steric hindrance.…”

“…a tendency consistent with the increasing density of the liquid. While the pre-peak follows this trend down to room-temperature, it's position qPP, which is related to the size of metaobjects via dPP=2π/qPP [25,26], settles at about 4.93±0.01 nm -1 at lower temperatures (see inset of Figure 4 (left)). This suggests a change in the kind of supramolecular arrangements, i.e.…”

“…This heterogeneity of the liquid on microscopic length scales is reflected in the strength of the so-called Debye process as observed in dielectric spectroscopy and can cause the appearance of a pre-peak in XRD intensities for lower momentum transfers than that of the first sharp diffraction peak (FSDP) [19]. Although being matter of research for a long time [20][21][22][23], recently the combination of dielectric spectroscopy, XRD and molecular dynamics simulations provided a deeper understanding on the formation of supramolecular arrangements on a structural level [24][25][26][27][28]. Interestingly, the microstructure observed in these liquids strongly depends on temperature [26,[29][30][31] and pressure [32,33].…”

“…Although being matter of research for a long time [20][21][22][23], recently the combination of dielectric spectroscopy, XRD and molecular dynamics simulations provided a deeper understanding on the formation of supramolecular arrangements on a structural level [24][25][26][27][28]. Interestingly, the microstructure observed in these liquids strongly depends on temperature [26,[29][30][31] and pressure [32,33]. However, diffraction studies of the pre-peak as indicator of supramolecular structure formation in alcohols by variation of the thermodynamic conditions are still scarce, particularly if pressure is concerned.…”

“…The position of the pre-peak was determined via a fit of a Pearson VII function on a linear slope as discussed in Ref. [26].…”