Figure 6.

Solid-state 2D ¹³C{¹H} LTMAS–HETCOR spectra of vacuum-dried 100%-amine–coCOF–H (a) after exposure to 100% ¹³C-enriched CO₂ for 12 h at 1 bar pressure and 298 K and (b) after desorption of CO₂ for 48 h by vacuum heating at 0.1 bar and 363 K. The spectra were acquired at 9.4 T, 8 kHz MAS, 95 K using short cross-polarization contact times of 500 μs. 1D ¹³C projections are shown along the horizontal axes for comparison with the 2D spectra, and 1D ¹H projections are shown along the vertical axes. Strong correlated ¹³C signal intensity (ca. 160 ppm) with ¹H signal at 12–14 ppm establishes that CO₂ chemisorbs to form a bicarbonate (HCO₃^–) species.