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To compensate for lacking experimental standard enthalpies of formation ΔfH° of haloboranes/−boranates as well as the isoelectronic halocarbenium ions and halomethanes, high-level quantum chemical calculations up to the ccsd(t)/(SDB-)aug-cc-pVQZ level have been performed to establish these values. Very reliable experimental data (e.g., ΔfH° of HCl, F, and CH4) or at the G3 level established values (e.g., ΔfH° of CF3+ = 410 kJ mol-1) were used as anchor points to obtain accurate absolute ΔfH° and mean bond enthalpy (mBE) values. To further minimize systematic errors of the protocol, all derived quantities were assessed in isodesmic reactions at the G3 and ccsd(t) level using the (SDB-)aug-cc-PVTZ basis set. The obtained ΔfH° values are in very good agreement to (scarcely available) accurate experimental and computational data. Almost all B-containing compounds have been assessed for the first time. We derived “best” ΔfH° values and used them to determine the mean E−X bond enthalpies in H4-nEXn-/0 and H3-nE...

We have designed and synthesized highly efficient organic sensitizers with a planar thienothiophene-vinylene-thienothiophene linker. Under standard global AM 1.5 solar conditions, the JK-113-sensitized cell gave a short circuit photocurrent density (J(sc)) of 17.61 mA cm(-2), an open-circuit voltage (V(oc)) of 0.71 V, and a fill factor (FF) of 72%, corresponding to an overall conversion efficiency (eta) of 9.1%. The incident monochromatic photo-to-current conversion efficiency (IPCE) of JK-113 exceeds 80% over the spectral region from 400 to 640 nm, reaching its maximum of 93% at 475 nm. The band tails off toward 770 nm, contributing to the broad spectral light harvesting. Solar-cell devices based on the sensitizer JK-113 in conjunction with a volatile electrolyte and a solvent-free ionic liquid electrolyte gave high conversion efficiencies of 9.1% and 7.9%, respectively. The JK-113-based solar cell fabricated using a solvent-free ionic liquid electrolyte showed excellent stability under light soaking at 60 degrees C for 1000 h.

To compensate for lacking experimental standard enthalpies of formation DeltafH degrees of haloboranes/-boranates as well as the isoelectronic halocarbenium ions and halomethanes, high-level quantum chemical calculations up to the ccsd(t)/(SDB-)aug-cc-pVQZ level have been performed to establish these values. Very reliable experimental data (e.g., DeltafH degrees of HCl, F, and CH4) or at the G3 level established values (e.g., DeltafH degrees of CF3+=410 kJ mol(-1)) were used as anchor points to obtain accurate absolute DeltafH degrees and mean bond enthalpy (mBE) values. To further minimize systematic errors of the protocol, all derived quantities were assessed in isodesmic reactions at the G3 and ccsd(t) level using the (SDB-)aug-cc-PVTZ basis set. The obtained DeltafH degrees values are in very good agreement to (scarcely available) accurate experimental and computational data. Almost all B-containing compounds have been assessed for the first time. We derived "best" DeltafH degrees values and used them to determine the mean E-X bond enthalpies in H4-nEXn-/0 and H3-nEXn0/+ (with n=1-3, E=B, C, and X=F-I). In each of the series, the DeltafH degrees values increase from fluorine to iodine, and except for the iodine-containing carbenium ions and the bromo- and iodomethanes, the DeltafH degrees values become lower with the more halogen atoms that are present in the particle. The boron containing species always have a lower DeltafH degrees than the isoelectronic carbenium ions and methanes, and the H4-nEXn-/0 are lower in energy than the parent H3-nEXn+/0. This reflects the greater average B-X bond strengths.

The metathesis reaction of Ag[(RO)3Al—F—Al(OR)3] and n-Bu4NBr in CH2Cl2 yields nearly quanti­tatively n-Bu4N+.[(RO)3Al—F—Al(OR)3]− [with R = C(CF3)3)] or (C16H36N)[Al2(C4F9O)6F]. In the asymmetric unit, two entire cations and four half-anions (one is disordered over two positions) are found. The intra­molecular distances are comparable to those found in other n-Bu4N+ or [(RO)3Al—F—Al(OR)3]− salts. Only weak inter­actions outside the sum of the van der Waals radii [r(F + H) = 2.6 A] are found between the cations and anions. The title compound is considerably soluble in CH2Cl2, which makes this salt a possible candidate as supporting electrolyte for electrochemical applications in nonpolar solvents. In addition, the [(RO)3Al—F—Al(OR)3]− anion is very stable against oxidation. Two CF3 groups of one anion are disordered over two positions; the site occupancy ratios are 0.64:0.36 and 0.78:0.22.