Structural Studies on the Basic Ionic Liquid 1-Ethyl-1,4-diazabicyclo[2.2.2]octanium Bis(trifluoromethylsulfonyl)imide and Its Bromide Precursor

The structure of 1-ethyl-1,4-diazabicyclo[2.2.2]­octanium bis­(trifluoromethylsulfonyl)­imide ([C₂DABCO]­[NTf₂]) was determined by single crystal X-ray diffraction, and its behavior with temperature was examined by synchrotron powder diffraction, differential scanning calorimetry (DSC), and Raman spectroscopy. [C₂DABCO]­[NTf₂] undergoes a solid–solid phase transition at 309 K and a solid–liquid (melting) transition at 350 K, as reported previously in the literature. The crystal structure of [C₂DABCO]­[NTf₂] was determined at temperatures below the solid–solid transition (solid-I phase), whereas in situ synchrotron powder diffraction enabled the unit cell of the solid phase observed above the solid–solid transition temperature (solid-II phase) to be indexed. High-resolution synchrotron powder diffraction data indicated the coexistence of a metastable phase with the solid-I and solid-II phases around the temperature of the solid–solid phase transition. A variable temperature Raman study suggested rotational movement of both [C₂DABCO]⁺ and [NTf₂]⁻ in the solid-II phase indicating the formation of a rotator phase. The structure of the [C₂DABCO]­[NTf₂] precursor 1-ethyl-1,4-diazabicyclo[2.2.2]­octanium bromide ([C₂DABCO]­[Br]) was also determined by single crystal X-ray diffraction and its phase transitions were examined by differential scanning calorimetry. A comparison of the structures and phase transitions of the two analogous salts provides insights into the relative electrostatic attraction between the ions and the relative packing density and efficiency in the crystal lattices

Structural Studies on the Basic Ionic Liquid 1-Ethyl-1,4-diazabicyclo[2.2.2]octanium Bis(trifluoromethylsulfonyl)imide and Its Bromide Precursor

The structure of 1-ethyl-1,4-diazabicyclo[2.2.2]­octanium bis­(trifluoromethylsulfonyl)­imide ([C₂DABCO]­[NTf₂]) was determined by single crystal X-ray diffraction, and its behavior with temperature was examined by synchrotron powder diffraction, differential scanning calorimetry (DSC), and Raman spectroscopy. [C₂DABCO]­[NTf₂] undergoes a solid–solid phase transition at 309 K and a solid–liquid (melting) transition at 350 K, as reported previously in the literature. The crystal structure of [C₂DABCO]­[NTf₂] was determined at temperatures below the solid–solid transition (solid-I phase), whereas in situ synchrotron powder diffraction enabled the unit cell of the solid phase observed above the solid–solid transition temperature (solid-II phase) to be indexed. High-resolution synchrotron powder diffraction data indicated the coexistence of a metastable phase with the solid-I and solid-II phases around the temperature of the solid–solid phase transition. A variable temperature Raman study suggested rotational movement of both [C₂DABCO]⁺ and [NTf₂]⁻ in the solid-II phase indicating the formation of a rotator phase. The structure of the [C₂DABCO]­[NTf₂] precursor 1-ethyl-1,4-diazabicyclo[2.2.2]­octanium bromide ([C₂DABCO]­[Br]) was also determined by single crystal X-ray diffraction and its phase transitions were examined by differential scanning calorimetry. A comparison of the structures and phase transitions of the two analogous salts provides insights into the relative electrostatic attraction between the ions and the relative packing density and efficiency in the crystal lattices

Structure of [C₄mpyr][NTf₂] Room-Temperature Ionic Liquid at Charged Gold Interfaces

The structure of 1-butyl-1-methylpyrrolidinium bis­(trifluoromethylsulfonyl)­imide ([C₄mpyr]­[NTf₂]) room-temperature ionic liquid at an electrified gold interface was studied using neutron reflectometry, cyclic voltammetry, and differential capacitance measurements. Subtle differences were observed between the reflectivity data collected on a gold electrode at three different applied potentials. Detailed analysis of the fitted reflectivity data reveals an excess of [C₄mpyr]⁺ at the interface, with the amount decreasing at increasingly positive potentials. A cation rich interface was found even at a positively charged electrode, which indicates a nonelectrostatic (specific) adsorption of [C₄mpyr]⁺ onto the gold electrode

Structural Studies on the Basic Ionic Liquid 1-Ethyl-1,4-diazabicyclo[2.2.2]octanium Bis(trifluoromethylsulfonyl)imide and Its Bromide Precursor

The structure of 1-ethyl-1,4-diazabicyclo[2.2.2]­octanium bis­(trifluoromethylsulfonyl)­imide ([C₂DABCO]­[NTf₂]) was determined by single crystal X-ray diffraction, and its behavior with temperature was examined by synchrotron powder diffraction, differential scanning calorimetry (DSC), and Raman spectroscopy. [C₂DABCO]­[NTf₂] undergoes a solid–solid phase transition at 309 K and a solid–liquid (melting) transition at 350 K, as reported previously in the literature. The crystal structure of [C₂DABCO]­[NTf₂] was determined at temperatures below the solid–solid transition (solid-I phase), whereas in situ synchrotron powder diffraction enabled the unit cell of the solid phase observed above the solid–solid transition temperature (solid-II phase) to be indexed. High-resolution synchrotron powder diffraction data indicated the coexistence of a metastable phase with the solid-I and solid-II phases around the temperature of the solid–solid phase transition. A variable temperature Raman study suggested rotational movement of both [C₂DABCO]⁺ and [NTf₂]⁻ in the solid-II phase indicating the formation of a rotator phase. The structure of the [C₂DABCO]­[NTf₂] precursor 1-ethyl-1,4-diazabicyclo[2.2.2]­octanium bromide ([C₂DABCO]­[Br]) was also determined by single crystal X-ray diffraction and its phase transitions were examined by differential scanning calorimetry. A comparison of the structures and phase transitions of the two analogous salts provides insights into the relative electrostatic attraction between the ions and the relative packing density and efficiency in the crystal lattices

Structure of [C₄mpyr][NTf₂] Room-Temperature Ionic Liquid at Charged Gold Interfaces

The structure of 1-butyl-1-methylpyrrolidinium bis­(trifluoromethylsulfonyl)­imide ([C₄mpyr]­[NTf₂]) room-temperature ionic liquid at an electrified gold interface was studied using neutron reflectometry, cyclic voltammetry, and differential capacitance measurements. Subtle differences were observed between the reflectivity data collected on a gold electrode at three different applied potentials. Detailed analysis of the fitted reflectivity data reveals an excess of [C₄mpyr]⁺ at the interface, with the amount decreasing at increasingly positive potentials. A cation rich interface was found even at a positively charged electrode, which indicates a nonelectrostatic (specific) adsorption of [C₄mpyr]⁺ onto the gold electrode

Structural Studies on the Basic Ionic Liquid 1-Ethyl-1,4-diazabicyclo[2.2.2]octanium Bis(trifluoromethylsulfonyl)imide and Its Bromide Precursor

The structure of 1-ethyl-1,4-diazabicyclo[2.2.2]­octanium bis­(trifluoromethylsulfonyl)­imide ([C₂DABCO]­[NTf₂]) was determined by single crystal X-ray diffraction, and its behavior with temperature was examined by synchrotron powder diffraction, differential scanning calorimetry (DSC), and Raman spectroscopy. [C₂DABCO]­[NTf₂] undergoes a solid–solid phase transition at 309 K and a solid–liquid (melting) transition at 350 K, as reported previously in the literature. The crystal structure of [C₂DABCO]­[NTf₂] was determined at temperatures below the solid–solid transition (solid-I phase), whereas in situ synchrotron powder diffraction enabled the unit cell of the solid phase observed above the solid–solid transition temperature (solid-II phase) to be indexed. High-resolution synchrotron powder diffraction data indicated the coexistence of a metastable phase with the solid-I and solid-II phases around the temperature of the solid–solid phase transition. A variable temperature Raman study suggested rotational movement of both [C₂DABCO]⁺ and [NTf₂]⁻ in the solid-II phase indicating the formation of a rotator phase. The structure of the [C₂DABCO]­[NTf₂] precursor 1-ethyl-1,4-diazabicyclo[2.2.2]­octanium bromide ([C₂DABCO]­[Br]) was also determined by single crystal X-ray diffraction and its phase transitions were examined by differential scanning calorimetry. A comparison of the structures and phase transitions of the two analogous salts provides insights into the relative electrostatic attraction between the ions and the relative packing density and efficiency in the crystal lattices

Structure of [C₄mpyr][NTf₂] Room-Temperature Ionic Liquid at Charged Gold Interfaces

The structure of 1-butyl-1-methylpyrrolidinium bis­(trifluoromethylsulfonyl)­imide ([C₄mpyr]­[NTf₂]) room-temperature ionic liquid at an electrified gold interface was studied using neutron reflectometry, cyclic voltammetry, and differential capacitance measurements. Subtle differences were observed between the reflectivity data collected on a gold electrode at three different applied potentials. Detailed analysis of the fitted reflectivity data reveals an excess of [C₄mpyr]⁺ at the interface, with the amount decreasing at increasingly positive potentials. A cation rich interface was found even at a positively charged electrode, which indicates a nonelectrostatic (specific) adsorption of [C₄mpyr]⁺ onto the gold electrode

Structure of [C₄mpyr][NTf₂] Room-Temperature Ionic Liquid at Charged Gold Interfaces

The structure of 1-butyl-1-methylpyrrolidinium bis­(trifluoromethylsulfonyl)­imide ([C₄mpyr]­[NTf₂]) room-temperature ionic liquid at an electrified gold interface was studied using neutron reflectometry, cyclic voltammetry, and differential capacitance measurements. Subtle differences were observed between the reflectivity data collected on a gold electrode at three different applied potentials. Detailed analysis of the fitted reflectivity data reveals an excess of [C₄mpyr]⁺ at the interface, with the amount decreasing at increasingly positive potentials. A cation rich interface was found even at a positively charged electrode, which indicates a nonelectrostatic (specific) adsorption of [C₄mpyr]⁺ onto the gold electrode

Structural Studies on the Basic Ionic Liquid 1-Ethyl-1,4-diazabicyclo[2.2.2]octanium Bis(trifluoromethylsulfonyl)imide and Its Bromide Precursor

The structure of 1-ethyl-1,4-diazabicyclo[2.2.2]­octanium bis­(trifluoromethylsulfonyl)­imide ([C₂DABCO]­[NTf₂]) was determined by single crystal X-ray diffraction, and its behavior with temperature was examined by synchrotron powder diffraction, differential scanning calorimetry (DSC), and Raman spectroscopy. [C₂DABCO]­[NTf₂] undergoes a solid–solid phase transition at 309 K and a solid–liquid (melting) transition at 350 K, as reported previously in the literature. The crystal structure of [C₂DABCO]­[NTf₂] was determined at temperatures below the solid–solid transition (solid-I phase), whereas in situ synchrotron powder diffraction enabled the unit cell of the solid phase observed above the solid–solid transition temperature (solid-II phase) to be indexed. High-resolution synchrotron powder diffraction data indicated the coexistence of a metastable phase with the solid-I and solid-II phases around the temperature of the solid–solid phase transition. A variable temperature Raman study suggested rotational movement of both [C₂DABCO]⁺ and [NTf₂]⁻ in the solid-II phase indicating the formation of a rotator phase. The structure of the [C₂DABCO]­[NTf₂] precursor 1-ethyl-1,4-diazabicyclo[2.2.2]­octanium bromide ([C₂DABCO]­[Br]) was also determined by single crystal X-ray diffraction and its phase transitions were examined by differential scanning calorimetry. A comparison of the structures and phase transitions of the two analogous salts provides insights into the relative electrostatic attraction between the ions and the relative packing density and efficiency in the crystal lattices