Elucidating the mechanism behind the infrared spectral features and dynamics observed in the carbonyl stretch region of organic carbonates interacting with lithium ions.

Ultrafast infrared spectroscopy has become a very important tool for studying the structure and ultrafast dynamics in solution. In particular, it has been recently applied to investigate the molecular interactions and motions of lithium salts in organic carbonates. However, there has been a discrepancy in the molecular interpretation of the spectral features and dynamics derived from these spectroscopies.

Proving and Probing the Presence of the Elusive C-H⋅⋅⋅O Hydrogen Bond in Liquid Solutions at Room Temperature.

Hydrogen bonds (H bonds) play a major role in defining the structure and properties of many substances, as well as phenomena and processes. Traditional H bonds are ubiquitous in nature, yet the demonstration of weak H bonds that occur between a highly polarized C-H group and an electron-rich oxygen atom, has proven elusive. Detailed here are linear and nonlinear IR spectroscopy experiments that reveal the presence of H bonds between the chloroform C-H group and an amide carbonyl oxygen atom in solution at room temperature.

Molecular Structure, Chemical Exchange, and Conductivity Mechanism of High Concentration LiTFSI Electrolytes.

High concentration lithium electrolytes have been found to be good candidates for high energy density and high voltage lithium batteries. Recent studies have shown that limiting the free solvent molecules in the electrolytes prevents the degradation of the battery electrodes. However, the molecular level knowledge of the structure and dynamics of such an electrolyte system is limited, especially for electrolytes based on typical organic carbonates.

Molecular structure and ultrafast dynamics of sodium thiocyanate ion pairs formed in glymes of different lengths.

Glyme-based electrolytes are one of the promising candidates in the development of sodium ion batteries due to their compatibility with conventional graphite electrodes. Recent studies have shown that the chelation effect significantly affects the ion pair formation in these sodium-glyme based electrolytes. However, the solvation structure and dynamics of the sodium-glyme complex have yet to be fully characterized.