41 research outputs found
Quantification of particle-induced inflammatory stress response: a novel approach for toxicity testing of earth materials
Quantum Chemical and FTIR Spectroscopic Studies on the Linkage Isomerism of Carbon Monoxide in Alkali-Metal-Exchanged Zeolites: A Review of Current Research
Spectroscopic and Thermodynamic Characterization of Strontium Carbonyls Formed Upon Carbon Monoxide Adsorption on the Zeolite Sr-Y
Characterization of Gallosilicate MFI-Type Zeolites by IR Spectroscopy of Adsorbed Probe Molecules
Quantum Chemical and FTIR Spectroscopic Studies on the Linkage Isomerism of Carbon Monoxide in Alkali-Metal-Exchanged Zeolites: A Review of Current Research
When adsorbed (at a low temperature) on alkali-metal-exchanged zeolites, CO forms both M(CO)+ and M(OC)+ carbonyl species with the extra-framework alkali-metal cation of the zeolite. Both quantum chemical and experimental results show that C-bondend adducts are characterized by a CāO stretching IR band at a frequency higher than that of 2143 cm-1 for free CO, while for O-bonded adducts this IR band appears below 2143 cm-1. The cation-CO interaction energy is higher for M(CO)+ than for M(OC)+ carbonyls, although the corresponding difference decreases substantially when going from Li+ to Cs+. By means of variable-temperature FTIR spectroscopy, this energy difference was determined for several alkali-metal cations, and the existence of a thermal equilibrium between M(CO)+ and M(OC)+ species was established. The current state of research in this field is reviewed here, with a view to gain more insight into the thermal isomerization process
Post-synthesis modifications of SBA-15 carbon replicas: improving hydrogen storage by increasing microporous volume
Linkage Isomerism of Carbon Monoxide in Alkali-Metal- Exchanged Zeolites: A Review of Current Research
Abstract: When adsorbed (at a low temperature) on alkali-metal-exchanged zeolites, CO forms both M(CO) + and M(OC) + carbonyl species with the extra-framework alkali-metal cation of the zeolite. Both quantum chemical and experimental results show that C-bonded adducts are characterized by a CāO stretching IR band at a frequency higher than that of 2143 cm-1 for free CO, while for O-bonded adducts this IR band appears below 2143 cm-1. The cation-CO interaction energy is higher for M(CO) + than for M(OC) + carbonyls, although the corresponding difference decreases substantially when going from Li + to Cs +. By means of variable-temperature FTIR spectroscopy, this energy difference was determined for several alkali-metal cations, and the existence of a thermal equilibrium between M(CO) + and M(OC) + species was established. The current state of research in this field is reviewed here, with a view to gain more insight into the thermal isomerization process