Intermolecular Interactions between Eosin Y and Caffeine Using <sup><b>1</b></sup>H-NMR Spectroscopy

<table>UV-Vis spectra of 0.75 <i>μ</i>M eosin Y and mixtures of 0.75 <i>μ</i>M eosin Y and 0.42 mM and 11.25 mM caffeine showing a shift in <svg height="16.450001" id="M33" style="vertical-align:-3.3907pt" version="1.1" viewbox="0 0 32.700001 16.450001" width="32.700001" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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<g transform="matrix(.012,-0,0,-.012,9.45,16.25)"><path d="M797 0h-214v26q46 5 58 17.5t12 63.5v167q0 116 -88 116q-48 0 -112 -52q3 -18 3 -42v-195q0 -46 11 -58t53 -17v-26h-214v26q48 5 59.5 17t11.5 60v172q0 115 -88 115q-47 0 -109 -52v-235q0 -47 10 -59.5t48 -17.5v-26h-211v26q50 5 62.5 17t12.5 60v207q0 48 -9 59.5
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</svg> from 518 to 520 and 526 nm, respectively.</table>

International Journal of Spectroscopy

fig11

Figure 11

Figure 11: Intermolecular Interactions between Eosin Y and Caffeine Using <sup><b>1</b></sup>H-NMR Spectroscopy 

International Journal of Spectroscopy

Intermolecular Interactions between Eosin Y and Caffeine Using 1H-NMR Spectroscopy

Figure 11

Intermolecular Interactions between Eosin Y and Caffeine Using ¹H-NMR Spectroscopy