Effect of Counteranions on the Conformational Equilibrium of 1-Butyl-3-methylimidazolium-Based Ionic Liquids

<table>Temperature dependences of the integrated intensity ratio between the <svg height="11.6125" id="M65" style="vertical-align:-0.0pt" version="1.1" viewbox="0 0 22.762501 11.6125" width="22.762501" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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<g transform="matrix(.017,-0,0,-.017,.062,11.55)"><path d="M713 296l-5 -25q-47 -7 -59 -20t-23 -72l-15 -79q-9 -48 -3 -74q-15 -3 -55 -13t-63 -15t-59.5 -10t-70.5 -5q-149 0 -243 80t-94 220q0 169 127.5 276.5t336.5 107.5q91 0 206 -36l-10 -165l-29 -1q1 85 -47.5 126t-146.5 41q-153 0 -243.5 -97t-90.5 -242
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</svg> conformers of [bmim]<sup>+</sup> cation of pure [bmim][<i>X</i>] (<i>X</i> = BF<sub>4</sub> (▲), NO<sub>3</sub> (<i>⚫</i>), SCN (○), and CH<sub>3</sub>COO (□)). The straight lines represent the result of the least-squares analysis.</table>

International Journal of Spectroscopy

fig5

Figure 5

Figure 5: Effect of Counteranions on the Conformational Equilibrium of 1-Butyl-3-methylimidazolium-Based Ionic Liquids 