Anionic MOFs

The confinement effects of the narrow pore on the ILs and the ionic interactions between [BMIM] favor the open pore while the anion, [PF6], was attached to the open metal sites, was observed in a simulation study. It was ascertained that C02 was favorably attached to the [PF6] anions sites. The study demonstrated that IL/MOF composites are a potential candidate for C02 adsorption and have displayed significantly high CO2/N2 selectivity. To the best of our... 

From the temperature variation of the equilibrium constant, thermodynamic parameters for the reaction were also obtained. The extent of formation of [Mo(CO)5l]" was found to be cation-dependent, and while equilibrium constants of 39 and 21 atm L moF were obtained for Bu4P and pyH+, none of the anionic iodide complex was observed for Na. Despite this variation, there seemed to be no correlation between the concentration of [Mo(CO)5l]" and the rate of the catalytic carbonylation reaction. It was proposed that [Mo(CO)5] and [Mo(CO)5l] are spectator species, with the catalysis being initiated by [Mo(CO)5]. Based on the in situ spectroscopic results and kinetic data, a catalytic mechanism was suggested, involving radicals formed by inner sphere electron transfer between EtI and [Mo(CO)5]. 

Cation Anion Tempe- rature, (K) Conduc- tivity 1, mS cm Conduc- tivity method Viscosity m. <=p Viscosity method Density (P), g cm- Density method Molar conductivity (A), cm Q mof Walden product ( ) Ref... 

The shoulder observed in Fig. 5(a) at 2078 cm is assigned to the free CN ejected. The CN anion is only seen as a shoulder, as its extinction coefficient is much weaker than when it is bound within a complex. We determined an integrated absorption coefficient of 840 moF dm cm" for the CN band at 2080 cm" and an integrated absorption coefficient for Fe(CN)g of 97,000 mol dm cm . The integrated absorption coefficient for Fe(CN) was determined as 15,800 moF dm cm . These determinations of integrated absorption coefficients enable us, after deconvolution of the peaks observed thanks to a fitting procedure, to know exactly the concentrations of the different species detected. 

The discovery of what appears to be a thermodynamic threshold governing the intercalation of graphite by fluoro anions, MF,, has required the evaluation of the thermodynamic stability of a number of such species. Since germanium tetrafluoride and fluorine are intercalated, in combination, by graphite to form both GeFj" and GeFs ", the first and second fluoride ion affinities of that molecule are each of interest. Evaluation of the fluoride ion affinity of boron trifluoride by Altshuller yielded a value of-71 kcal moF. This has been accepted by several authors as the basis for other fluoride ion affinities and electron affinities. Sharpe, however, has preferred a value of -91 kcal moF, based upon the data of Bills and Cotton. Although this latter value is in harmony with other fluoride ion affinities and electron affinities, its confirmation was clearly desirable to provide a firm basis for correction of affinities based upon the lower value. This paper describes the studies that have provided these fluoride ion affinities. 

It was found that anion (2) has about 80 kJ moF more stabilization than the hypothetical model (19a). This shows that there is a substantial amount of stabilizing resonance energy, which is in accord with its having a cyclic 6ir-electron system. The stabilization is not great enough, however, for oxetene to be expected to show appreciable acidic properties. Calculations show oxetene to be less acidic than propene. 

---