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Utilizing the "ideal" ionic liquid salt bridge to measure Gibbs energies of transfer of silver ions between the solvents water, acetonitrile, propylene carbonate and dimethylformamide results in a consistent data set with a precision of 0.6 kJ mol -1 over 87 measurements in 10 half-cells. This forms the basis for a coherent experimental thermodynamic framework of ion solvation chemistry. In addition, we define the solvent independent pe abs H 2 O - and the E abs H 2 O values that account for the electronating potential of any redox system similar to the pH abs H 2 O value of a medium that accounts for its protonating potential. This E abs H 2 O scale is thermodynamically well-defined enabling a straightforward comparison of the redox potentials (reducities) of all media with respect to the aqueous redox potential scale, hence unifying all conventional solvents' redox potential scales. Thus, using the Gibbs energy of transfer of the silver ion published herein, one can convert and unify all hitherto published redox potentials measured, for example, against ferrocene, to the E abs H 2 O scale., (© 2022 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

Herein we present the molecular structures of six neutral Lewis acid-base adducts of the Lewis superacid Al(N(C 6 F 5 ) 2 ) 3 and its higher homolog Ga(N(C 6 F 5 ) 2 ) 3 with the electron pair donors MeCN, CN t Bu, THF and PMe 3 . The crystal structures reveal crucial structural changes compared to the free Lewis acids as a consequence of the adduct formation. Furthermore, we calculated the corresponding dissociation enthalpies of the adducts which lie between 69 and 141 kJ mol -1 and are therefore considerably lower compared to the values for the formation of the anionic fluoride or chloride metallates.

In this work, we perform first-principle density functional theory calculations with the Perdew-Burke-Ernzerhof (PBE) exchange correlation functional to compare the results of the gauge-including atomic orbital (GIAO) method with the gauge-including projector-augmented wave (GIPAW) approach for isotropic 11 B nuclear magnetic resonance shifts. GIPAW had been used successfully for the theoretical calculation of nuclear magnetic parameters of 11 B species in strong ionic solid-phase compounds such as borates but had been applied very rarely to structures where boron is mainly involved in complex covalent bonding situations, for example, in icosahedra of boron-rich borides. Thus, we investigate the accuracy of both well-known methods and reliability of the effective treatment of core electrons on a test set containing 16 experimentally known closo -(hetero)dodecaboranes. In general, we find very good agreement between GIAO and GIPAW when compared to experimental observations. However, accidental degeneracies of the shift values are better predicted by GIPAW. The optimized molecular geometries on the PBE level agree well with gaseous electron diffraction data and lead to theoretical isotropic chemical 11 B shifts with root-mean-square errors of 2.1 and 1.0 ppm depending on the used model of converting absolute shieldings to chemical shifts. The comparison with results from hybrid functionals (B3LYP, B3LYP-D2, and PBE0) shows a minor improvement in accuracy, which is in agreement with 13 C shifts of sp 3 -hybridized species. In order to prove the reliability of the conversion parameters obtained by PBE, we report the calculated 11 B shifts of 1,2-, 1,7-, and 1,12-PCB 10 H 11 with GIAO and GIPAW to our knowledge for the first time. Additionally, Bader's analysis is carried out on the converged electron density for all boron species within the molecular test set, yielding no simple direct relation between charge and isotropic shifts.

The reaction of the Ga + source [Ga(PhF) 2 ] + [Al(OR F ) 4 ] - with the neutral σ-donor ligand dmap (4-Me 2 N-C 6 H 4 N) produces the unexpectedly large and fivefold positively charged cluster cation salt [Ga 5 (dmap) 10 ] 5+ ([Al(OR F ) 4 ] - ) 5 . It includes a regular and planar Ga 5 pentagon with strong metal-metal bonding. Additionally, the compound represents the first salt in which an ionic 1:5 packing is realized. We discuss the nature of this structure which results from the conversion of the non-bonding 4s 2 lone-pair orbitals into fully Ga-Ga-bonding orbitals and the solid-state arrangement of the ions constituting the lattice as an almost orthohexagonal AX 5 lattice, possibly the aristotype of any 5:1 salt., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

Homoleptic carbonyl radical cations are a textbook family of complexes hitherto unknown in the condensed phase, leaving their properties and applications fundamentally unexplored. Here we report on two stable 17-electron [Cr(CO) 6 ] •+ salts that were synthesized by oxidation of Cr(CO) 6 with [NO] + [Al(OR F ) 4 ] - (R F  = C(CF 3 ) 3 )) in CH 2 Cl 2 and with removal of NO gas. Longer reaction times led to NO/CO ligand exchange and formation of the thermodynamically more stable 18-electron species [Cr(CO) 5 (NO)] + , which belongs to the family of heteroleptic chromium carbonyl/nitrosyl cations. All salts were fully characterized (IR, Raman, EPR, NMR, scXRD, pXRD, magnetics) and are stable at room temperature under inert conditions over months. The facile synthesis of these species enables the thorough investigation of their properties and applications to a broad scientific community.

Reduction of 2,6-bis(diazaboryl)pyridine with KC8 gives a room-temperature-stable yellow colored solution containing the corresponding radical anion. The radical was characterized by single crystal XRD, EPR spectroscopy, UV-vis absorption spectroscopy and electrochemically, supported by theoretical calculations. The negative charge and spin density are mainly distributed over the atoms of the pyridine ring, making this the first isolated pyridine radical anion as its potassium salt.

Instead of yielding the desired non-classical silylium ions, the reactions of different alkenes/alkynes with several [Me 3 Si] + sources mostly led to oligomerization, or - in the presence of Me 3 SiH - hydrosilylation of the alkenes/alkynes. Yet, from the reaction of 2-butyne with ion-like Me 3 Si-F-Al(OR F ) 3 (R F = C(CF 3 ) 3 ) the salt of the silylated tetramethyl cyclobutenyl cation [Me 4 C 4 -SiMe 3 ] + [ al - f - al ] - 1 ([ al - f - al ] - = [(R F O) 3 Al-F-Al(OR F ) 3 ] - ) was obtained in good yield (NMR, scXRD, Raman, and IR). All the experimental and calculated evidence suggest a mechanism in which 1 was formed via a non-classical silylium ion as an intermediate. The removal of the [Me 3 Si] + moiety from the cation in 1 was investigated as a means to provide free tetramethyl cyclobutadiene (CBD). However, the addition of [NMe 4 ]F, in order to release Me 3 SiF and form CBD, led to the unexpected deprotonation of the cation. The addition of 4-dimethylaminopyridine to remove the [Me 3 Si] + cation as a Lewis acid/base adduct, led to an adduct with the four-membered ring in the direct neighborhood of the Me 3 Si group. By the addition of Et 2 O to a solution of 1 , the [F-Al(OR F ) 3 ] - anion (and Et 2 O-Al(OR F ) 3 ) was generated from the [ al - f - al ] - counterion. Subsequently, the [F-Al(OR F ) 3 ] - anion abstracted the [Me 3 Si] + moiety from [Me 4 C 4 -SiMe 3 ] + , probably releasing CBD. However, due to the immediate reaction of CBD with [Me 4 C 4 -SiMe 3 ] + and subsequent oligomerization, it was not possible to use CBD in follow-up chemistry., (This journal is © The Royal Society of Chemistry 2019.)

IR spectroscopic studies of the gaseous metal carbonyl cations [Co(CO) 5 ] + ⋅mCO (m=1-4) indicated that the weakly bound CO molecules in a second coordination sphere perturb the structure of [Co(CO) 5 ] + causing the CO stretching frequencies ν(CO) to become noticeably redshifted. In this work, we aimed to establish the relationship between such gas phase IR spectra and those recorded in condensed phases, either as a solid salt or as a solution in the weakly basic solvent o-difluorobenzene. For this purpose, a series of [Co(CO) 5 ] + [WCA] - salts (WCA=weakly coordinating anion), with the counterions varying between more coordinating (WCA=F-Al(OR F ) 3 , (R F O) 3 Al-F-Al(F)(OR F ) 2 ; R F =C(CF 3 ) 3 ) and almost non-coordinating (WCA=Al(OR F ) 4 , F{Al(OR F ) 3 } 2 ), were synthesized and characterized by vibrational spectroscopy as well as X-ray structure analysis. The experimental spectra differ considerably from that of the undisturbed gaseous [Co(CO) 5 ] + ion, as the structural deformation of [Co(CO) 5 ] + requires very little energy. Together with previously reported data, the perturbed condensed phase [Co(CO) 5 ] + ions were analyzed and compared with the gaseous [Co(CO) 5 ] + ⋅mCO ions. DFT calculations were performed on simply adapted [Co(CO) 5 ] + structures to allow the assignment of all the ν(CO) modes and a qualitative interpretation of structural deformations by external influences as a function of the environment (ligands, solvation, crystal packing). The analysis showed that especially the degenerate E' mode ν e and the averaged asymmetric equatorial CO stretch ν ‾ e , which originates from a split of the E' mode, are a function of the interaction with the environment. Whereas for the more coordinating counterions ν ‾ e values of 2112-2120 cm -1 were obtained, for the less coordinating counterions ν ‾ e values of up to 2133 cm -1 were found, which is very close to that of gaseous [Co(CO) 5 ] + ⋅4CO, with a ν ‾ e value of 2135 cm -1 . This indicates the possibility of approximating the gas phase conditions in the condensed phases with the [Co(CO) 5 ] + ion probably being the prototypical probe molecule for investigating the strengths of interactions in different environments., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The univalent salt Ga(PhF) 2 + [Al(OR F ) 4 ] - (R F =OC(CF 3 ) 3 ) forms the strongly metal-metal bonded cluster tetracations [Ga II 2 (L) 4 ] 4+ and [Ga I 4 (L') 8 ] 4+ , when it reacts with innocent ligands like phenanthroline (L=phen) or t-butylisonitrile (L'= t Bu-NC). Their structures and energetics are discussed as a function of the employed ligands, supported by DFT calculations and Born-Fajans-Haber cycles., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: Since Braithwaite advanced reintegrative shaming theory about 25 years ago, the theory has almost invariably been retested only in relation to predatory offending. Few studies have tested the relevance of the theory for non-predatory offending., Aim: This study aims to explore the utility of reintegrative shaming theory in explaining non-predatory crimes. Our main research question was: is acknowledgement of shame apportioned by others associated with reduction in non-predatory offending?, Methods: We used zero-inflated negative binomial modelling to analyse data from a national, longitudinal, population-based study of 1,726 adolescents., Results: Overall, peer shame acknowledgement at age 18-21 was a significant predictor of no non-predatory offending at ages 21-27. Contrary to our expectation, however, similar recognition and incorporation of parental shame was not related to absence of such offending., Implications: Our findings add further weight to the validity of reintegrative shaming theory, showing its broader value explaining criminal behaviour-and desistance from it-beyond the original model., (Copyright © 2018 John Wiley & Sons, Ltd.)

Oxymethylene dimethyl ethers (OME n ; CH 3 (-OCH 2 -) n O-CH 3 , n=3-5) are a novel class of sustainable synthetic fuels, which are of increasing interest due to their soot-free combustion. Herein a novel anhydrous OME n synthesis route is presented. Catalyzed by trimethyloxonium salts, dimethoxymethane takes up monomeric gaseous formaldehyde instantaneously and forms high purity OME n at temperatures of 25-30 °C. This new anhydrous approach using molecular formaldehyde and catalytic amounts of highly active trimethyloxonium salts represents a promising new step towards a sustainable formation of OME n emanating from CO 2 and H 2 ., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The synthesis and structural characterization of the hitherto unknown parent Co(bz) 2 + (bz=benzene) complex and several of its derivatives are described. Their synthesis starts either from a CoCO 5 + salt, or directly from Co 2 (CO) 8 and a Ag + salt. Stability and solubility of these complexes was achieved by using the weakly coordinating anions (WCAs) [Al(OR F ) 4 ] - and [F{Al(OR F ) 3 } 2 ] - {R F =C(CF 3 ) 3 } and the solvent ortho-difluorobenzene (o-DFB). The magnetic properties of Co(bz) 2 + were measured and compared in the condensed and gas phases. The weakly bound Co(o-dfb) 2 + salts are of particular interest for the preparation of further Co I salts, for example, the structurally characterized low-coordinate 12 valence electron Co(P t Bu 3 ) 2 + and Co(NHC) 2 + salts., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

This Review provides a unified view on Brønsted acidity. For this purpose, a brief overview of the concepts acidity, acid strengths, and pH value is given, including problems, proposed solutions, and the use of the pH abs /pHabsH2O scale as a unifying concept. Thereafter, some examples of the accessibility and application of unified pH abs values are given. The Review is rounded off with the analogy of acid-base chemistry to redox chemistry with the introduction of the unified redox scale pe abs . The combination of pH abs and pe abs values in the protoelectric potential map (PPM), as elaborated in ongoing studies on the thermochemistry of single ions, provides a means to classify and to compare all possible acid-base/redox reactions in a medium-independent and, thus, unified fashion., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The computational investigation of a titanium-catalysed reductive radical-radical coupling is reported. The results match the conclusions from an earlier experimental study and enable a further interpretation of the previously observed complex reaction kinetics. Furthermore, the interplay between neutral and cationic reaction pathways in titanium(iii)-catalysed reactions is investigated for the first time. The results show that hydrochloride additives and reaction byproducts play an important role in the respective equilibria. A full reaction profile is assembled and the computed activation barrier is found to be in reasonable agreement with the experiment. The conclusions are of fundamental importance to the field of low-valent titanium catalysis and the understanding of related catalytic radical-radical coupling reactions.

An important intermediate goal to evaluate our concept for the assumption-free determination of single-ion Gibbs transfer energies Δ tr G°(i, S 1 →S 2 ) is presented. We executed the crucial steps a) and b) of the methodology, described in Part I of this treatise, exemplarily for Ag + and Cl - with S 1 being water and S 2 being acetonitrile. The experiments showed that virtually all parts of the liquid junction potentials (LJPs) at both ends of a salt bridge cancel, if the bridge electrolyte is an "ideal" ionic liquid, that is, one with nearly identical diffusion of anion and cation. This ideality holds for [N 2225 ] + [NTf 2 ] - in the pure IL, but also in water and acetonitrile solution. Electromotive force measurements of solvation cells between S 1 and S 2 demonstrated Nernstian behavior for Ag + concentration cells and constant like cell potentials for solutions with five tested Ag + counterions., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Described is a procedure for the thermodynamically rigorous, experimental determination of the Gibbs energy of transfer of single ions between solvents. The method is based on potential difference measurements between two electrochemical half cells with different solvents connected by an ideal ionic liquid salt bridge (ILSB). Discussed are the specific requirements for the IL with regard to the procedure, thus ensuring that the liquid junction potentials (LJP) at both ends of the ILSB are mostly canceled. The remaining parts of the LJPs can be determined by separate electromotive force measurements. No extra-thermodynamic assumptions are necessary for this procedure. The accuracy of the measurements depends, amongst others, on the ideality of the IL used, as shown in our companion paper Part II., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We present a new implementation of the template localization for the fully automated and parallizable incremental method, which excludes failures of this important step within the domain-specific basis set approach and thus ensures a higher reliability of the scheme, preserving its very high accuracy. Furthermore, we combine our method with an efficient focal-point ansatz to reach the complete basis set limit and carefully assess this approach for the first time with regard to reaction energies. For a test set of 51 reactions the incremental focal-point method with a basis set of moderate size provides a very high accuracy with respect to the complete basis set limit. That way, we are finally able to apply the scheme as a benchmark method (e.g., for density functionals) in the context of a relevant chemical topic, the intramolecular decomposition of tris-perfluoro-tert-butoxyalane (43 heavy atoms, 352 electrons).

The recently published purely metallo-organic Ni I salt [Ni(cod) 2 ][Al(OR F ) 4 ] (1, cod=1,5-cyclooctadiene, R F =C(CF 3 ) 3 ) provides a starting point for a new synthesis strategy leading to Ni I phosphine complexes, replacing cod ligands by phosphines. Clearly visible colour changes indicate reactions within minutes, while quantum chemical calculations (PBE0-D3(BJ)/def2-TZVPP) approve exergonic reaction enthalpies in all performed ligand exchange reactions. Hence, [Ni(dppp) 2 ][Al(OR F ) 4 ] (2, dppp=1,3-bis(diphenylphosphino)propane), [Ni(dppe) 2 ][Al(OR F ) 4 ] (3, dppe=1,3-bis(diphenyl-phosphino)ethane), three-coordinate [Ni(PPh 3 ) 3 ][Al(OR F ) 4 ] (4) and a remarkable two-coordinate Ni I phosphine complex [Ni(PtBu 3 ) 2 ][Al(OR F ) 4 ] (5) were characterised by single crystal X-ray structure analysis. EPR studies were performed, confirming a nickel d 9 -configuration in complexes 2, 4 and 5. This result is supported by additional magnetization measurements of 4 and 5. Further investigations by cyclic voltammetry indicate relatively high oxidation potentials for these Ni I compounds between 0.7 and 1.7 V versus Fc/Fc + . Screening reactions with O 2 and CO gave first insights on the reaction behaviour of the Ni I phosphine complexes towards small molecules with formation of mixed phosphine-CO-Ni I complexes and oxidation processes yielding new Ni I and/or Ni II derivatives. Moreover, 4 reacted with CH 2 Cl 2 at RT to give a dimeric Ni II ylide complex (4 c). As CH 2 Cl 2 is a rather stable alkyl halide with relatively high C-Cl bond energies, 4 appears to be a suitable reagent for more general C-Cl bond activation reactions., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Herein we present the synthesis of the two Lewis acids Al[N(C 6 F 5 ) 2 ] 3 (ALTA) and Ga[N(C 6 F 5 ) 2 ] 3 (GATA) via salt elimination reactions. The metal complexes were characterized by NMR-spectroscopic methods and X-ray diffraction analysis revealing the stabilization of the highly Lewis acidic metal centers by secondary metal-fluorine contacts. The Lewis acidic properties of Al[N(C 6 F 5 ) 2 ] 3 and Ga[N(C 6 F 5 ) 2 ] 3 are demonstrated by reactions with Lewis bases resulting in the formation of metallates accompanied by crucial structural changes. The two metallates [Cs(Tol) 3 ] + [FAl(N(C 6 F 5 ) 2 ) 3 ] - and [AsPh 4 ] + [ClGa(N(C 6 F 5 ) 2 ) 3 ] - contain interesting weakly coordinating anions. The reaction of Al[N(C 6 F 5 ) 2 ] 3 with trityl fluoride yielded [CPh 3 ] + [FAl(N(C 6 F 5 ) 2 ) 3 ] - which could find application in the activation of metallocene polymerization catalysts. The qualitative Lewis acidity of Al[N(C 6 F 5 ) 2 ] 3 and Ga[N(C 6 F 5 ) 2 ] 3 was investigated by means of competition experiments for chloride ions in solution. DFT calculations yielded fluoride ion affinities in the gas phase (FIA) of 555 kJ mol -1 for Al[N(C 6 F 5 ) 2 ] 3 and 472 kJ mol -1 for Ga[N(C 6 F 5 ) 2 ] 3 . Thus, Al[N(C 6 F 5 ) 2 ] 3 can be considered a Lewis superacid with a fluoride affinity higher than SbF 5 (493 kJ mol -1 ) whereas the FIA of the corresponding gallium complex is slightly below the threshold to Lewis superacidity.

The facile synthesis of a pentacarbonyl cobalt(I) salt without the need for a superacid as solvent is presented. This salt, [Co(CO) 5 ] + [Al(OR F ) 4 ] - {R F =C(CF 3 ) 3 }, readily accessible on a multigram scale, undergoes substitution reactions with arenes yielding the hitherto unknown class of two-legged cobalt piano-stool complexes [(arene)Co(CO) 2 ] + with four different arene ligands. Such a substitution chemistry would have been impossible in superacid solution, as the arenes used would have been oxidized and/or protonated. Thus, the general approach described herein may have a wide synthetic use. Additionally, the thermochemistry of the piano-stool complexes is shown to be not easy to describe computationally and most of the established DFT methods overestimate the reaction energies. Only CCSD(T) calculations close to the basis set limit gave energies fully agreeing with the experiment., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)