Low-temperature13C NMR investigations on carbon monoxide hydrogen bonded to Brønsted acid sites in HY zeolites

Multiple Modes of Motion: Realizing the Dynamics of CO Adsorbed in M‐MOF‐74 (M = Mg, Zn) by Using Solid‐State NMR Spectroscopy

“…13 C SSNMR spectroscopy has been used to study the binding affinity and rigidity of CO and CO 2 in copper‐based MOFs,11 along with the local environments, exchange, and binding modes of CO in a rhodium‐exchanged NaY zeolite 12. The adsorption of CO within H‐Y zeolites13 has been probed by 13 C SSNMR spectroscopy, which was also used to understand the role of CO in the carbonylation of alcohols and olefins in the zeolite H‐ZSM‐514 and in the catalytic conversion of methanol to hydrocarbons on unmodified ZSM‐5 15 . 13 C SSNMR spectroscopy has been used to gain further insight into how CO affects n ‐pentane conversion to hydrocarbons on sulfated zirconia 16 .…”

Combined Solid-State NMR and Computational Approach for Probing the CO2 Binding Sites in a Porous-Organic Polymer

“…4 ppm) was predicted by calculation for a static CO 2 •••N interaction (see the Experimental Section for further details) with respect to free pyridine nitrogen atom in agreement with the very poor polarizing ability of the CO 2 molecule. However, because of the broad peaks observed in the experimental 15 no significant differences can be reliably identified between the degassed sample and that loaded with 800 bar 13 CO 2 (Figure S1 in the Supporting Information). 2D 1 H− 13 C on-and off-resonance FSLG HETCOR spectra (Figures S2 and S3, respectively, in the Supporting Information) provided further support to our proposed scheme for 13 CO 2 binding inside the POP because they directly allowed the recognition of the adsorption site.…”

“…An echo pulse sequence (90-τ-180-τ-acq; 1 H 90°= 0.77 μs, 1 H 180°= 1.54 μs) was used to suppress the probe background signal. 1 H, 13 C, and 15 N chemical shift scales were referenced with the resonance of adamantane ( 1 H signal at 1.87 ppm), hexamethylbenzene ( 13 C methyl signal at 17.4 ppm), and glycine ( 15 N signal at δ = 33.4 ppm with respect to NH 3 ) as external standards.…”

“…Calculations of the magnetic shielding σ were performed on the model structure (i.e., without CO 2 ) and on the structure shown in Figure 5a using the GIAO (gauge-including atomic orbital) 22 method at the 6-311++G(2d,2p) level. The theoretical absolute magnetic shielding (σ) values were converted into 15 N chemical shifts (δ) relative to the absolute magnetic shielding of the reference substance NH 3 (σ = 257.8 ppm, δ = 0 ppm) computed at the same level.…”

“…The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.jpcc.7b00660. 15…”