Article
Chemistry, Multidisciplinary
Luong Phong Ho, Matthias Tamm
Summary: This article provides a brief overview of the design and preparation of N-heterocyclic carbenes carrying weakly coordinating anions, and summarizes numerous transition metal and main group element complexes isolated in the past decade.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Skyler D. D. Ware, Wendy Zhang, David J. J. Charboneau, Channing K. K. Klein, Sarah E. E. Reisman, Kimberly A. A. See
Summary: This study investigates factors influencing the electrochemical reduction of Sm(III) to Sm(II), including the effects of supporting electrolyte, electrode material, and Sm precursor. The coordination strength of the counteranion of the Sm salt is found to affect the reversibility and redox potential of the Sm(II)/(III) couple, and the counteranion primarily determines the reducibility of Sm(III). Electrochemically generated SmI2 performs similarly to commercial SmI2 solutions in a proof-of-concept reaction.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Physical
Frederik Bader, Jean Christophe Tremblay, Beate Paulus
Summary: The presence of a host environment can affect the properties of molecules. In this study, the structure and vibrational properties of trifluoride in cryogenic argon environments were investigated through calculations and experiments. The results show that the properties of trifluoride are dependent on the specific argon environment, indicating a delicate influence of the host atoms on the guest molecule.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Jakub Brzeski
Summary: Quantum-chemical calculations were used to investigate the acidity and stability of aluminabenzene-based Lewis acids and anions. Aluminabenzene was found to be a stronger Lewis superacid than antimony pentafluoride, and electron-withdrawing substitutions on the heterocyclic ring led to the formation of extremely strong Lewis superacids. Two of these molecules, AlC5Cl5 and AlC5(CN)(5), were identified as the strongest Lewis acids reported in the literature. Addition of fluoride anion to substituted aluminabenzene-based Lewis acids resulted in the formation of anions with lower electronic stability but higher thermodynamic stability, making them suitable as counterions for reactive cations. The proposed Lewis acids may undergo isomerization and dimerization, while the studied anions are expected to remain stable against such processes.
JOURNAL OF COMPUTATIONAL CHEMISTRY
(2023)
Article
Crystallography
Emmanuel Adeniyi, Matthias Zeller, Sergiy V. V. Rosokha
Summary: An X-ray structural analysis revealed that salts of TMPD, MPTZ, and OMB with dodecamethyl- or hexabromo-substituted carbadodecaborate anions have layered structures. The cationic layers contain either well-separated TMPD+ or MPTZ(+) cation radicals or pi-stacks of partially oxidized OMB moieties. Quantum mechanical calculations showed that the formation of isolated cation radicals or pi-bonded associations in these salts is correlated with the strength of multicenter pi-bonding.
Article
Chemistry, Multidisciplinary
Vasileios Balos, Naveen Kumar Kaliannan, Hossam Elgabarty, Martin Wolf, Thomas D. Kuehne, Mohsen Sajadi
Summary: The solvation of ions alters the properties of water, and the underlying mechanism is believed to be the disruption of water's hydrogen-bonding network caused by ions. This study investigates the dissipation of energy in salt solutions and reveals that highly charged cations enhance the rotational-to-translational energy transfer, while highly charged anions reduce it. Molecular dynamics simulations provide insights into the changes in the hydrogen-bond strength between water molecules induced by cations and anions.
Article
Chemistry, Multidisciplinary
M. Milagros Muriel-Olaya, Ibon Alkorta, Jose Elguero
Summary: Six stationary points in the thermal energy profile of F-8-COT were explored, including three minima and three transition states corresponding to its transformation into F-8-BOT and F-8-TCO. The formation of anion-pi complexes in the reaction profile was investigated, and the results were rationalized using electrostatic potential and thermodynamic cycles. Additionally, electron density analysis was conducted using the AIM methodology.
Article
Chemistry, Organic
Stephen H. Dempsey, Steven R. Kass
Summary: In this study, the dissociation enthalpies of weakly coordinating cations were computed, and their performances were compared. The results showed that substituted tetraphenylphosphonium ion derivatives are effective weakly coordinating cations that perform as well as or even better than P2 and P5 phosphazenium ions.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Helmut Poleschner, Konrad Seppelt
Summary: Thiiranium and seleniranium salts were synthesized from different starting materials and their reactions were investigated, revealing unexpected products due to attempts to cleave specific groups. The study highlights the complexity of reactions in this system.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Physical
Juan J. J. Aucar, Alejandro F. F. Maldonado, Juan I. I. Melo
Summary: In this work, relativistic corrections to the electric field gradient (EFG) are presented, including spin-dependent corrections for the first time. The results show that these new corrections significantly improve the performance of the existing method and are in close agreement with calculations at the four-component Dirac-Hartree-Fock (4c-DHF) level. The accuracy of the EFG values obtained with this new method allows for the analysis of the electronic origin of relativistic effects using well-known nonrelativistic operators.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Sergi Burguera, Antonio Bauza, Antonio Frontera
Summary: This study provides evidence that Hg(II)& sdot;& sdot;& sdot;d(8)[M] interactions should be more accurately described as spodium bonds.
Article
Chemistry, Inorganic & Nuclear
Iwona Anusiewicz, Piotr Skurski
Summary: The stability and structure of polynuclear anions composed of ScF3 building blocks were investigated using advanced electronic structure methods. The study revealed the most stable isomers, which have compact structures and a large number of bridging linkages. Additionally, it was found that the electron detachment energies of these anions increase with the number of ScF3 building blocks involved. The thermodynamic stability of the anions was also verified.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Jing Shang, Congxin Xia, Chun Tang, Chun Li, Yandong Ma, Yuantong Gu, Liangzhi Kou
Summary: The bending deformation of AgBiP2Se6 monolayers can manipulate the polarization direction and domain size, significantly improving the ferroelectric stability. This mechano-ferroelectric coupling represents a new mechanism for stabilization and polarization flip in 2D ferroelectrics, with potential applications in next-generation non-volatile storage devices.
NANOSCALE HORIZONS
(2021)
Article
Chemistry, Multidisciplinary
Rocio Sanchez-de-Armas, Nicolas Montenegro-Pohlhammer, Aysegul Develioglu, Enrique Burzuri, Carmen J. Calzado
Summary: This study investigates the integration of SCO molecules on active nanodevices through quantum chemistry calculations, focusing on the encapsulation of Fe(ii) spin-crossover complexes in single-walled carbon nanotubes. The research reveals that the applied external electric field affects the spin-transition, and the local conditions of the substrate impact the transport properties.
Article
Chemistry, Physical
Alexander Bakulin, Lora S. Chumakova, Svetlana E. Kulkova
Summary: The oxygen absorption energy and migration barriers in titanium silicide with composition Ti5Si3 and hexagonal structure have been calculated, and the diffusion mechanism of oxygen in this material has been discussed. The obtained diffusion coefficient of oxygen in Ti5Si3 is comparable to experimental values for metal oxides.
Article
Chemistry, Multidisciplinary
Manuel Schmitt, Ingo Krossing
Summary: The metal dinitrogen bonding in a wide series of terminal end-on dinitrogen complexes was investigated using charge displacement analysis. The effect of sigma donation and pi backdonation on the N-N bond was discussed and compared with observations for carbonyl complexes. It was found that sigma donation had no significant effect on the N-N bond strength, whereas pi backdonation caused elongation of the N-N bond.
JOURNAL OF COMPUTATIONAL CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Philipp Dabringhaus, Silja Zedlitz, Luisa Giarrana, David Scheschkewitz, Ingo Krossing
Summary: Schnockel's [(AlCp*)(4)] and Jutzi's [SiCp*][B(C6F5)(4)] are important in modern main-group chemistry with various applications in synthesis and catalysis. However, the reactivity between AlCp* and [SiCp*](+) has not been explored. In this study, their reaction was investigated and complex salts [Cp*Si(AlCp*)(3)][WCA] were obtained. The tetrahedral [SiAl3](+) core not only represents a rare example of a low-valent silicon-doped aluminium-cluster, but also provides a convenient preparative entry towards low-valent Si-Al clusters.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Antoine Barthelemy, Harald Scherer, Hanna Weller, Ingo Krossing
Summary: This study presents the synthesis and characterization of two salts [(L)GaGa(L)][Al(ORF)(4)]2 ([pf]- = [Al(ORF)(4)]-), which include the first dicationic digallene [(L)Ga?Ga(L)]2+ and a digallane [(L)Ga-Ga(L)]2+. The dicationic digallene features a trans-bent [L-GaGa-L]2+ bond analogous to neutral R-GaGa-R molecules and similar to Robinson's famous Digallyne [R-GaGa-R]2-. The dicationic digallane is similar to the widely used Jones magnesium dimer but has a very short Ga-II-Ga-II single bond.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Timm M. Reichenau, Felix Steinke, Michael T. Wharmby, Christian Naether, Tobias A. Engesser, Norbert Stock
Summary: A concept for obtaining isoreticular compounds with tri-instead of tetravalent metal cations using highly acidic reaction conditions was developed and successfully applied in a high throughput study. This study led to the discovery of a new porous aluminium phosphonate denoted CAU-60·6HCl. The compound demonstrated reversible desorption of HCl, with varying compositions observed and high stability when adsorbing HBr.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Dustin Kubas, Malte Semmel, Ouda Salem, Ingo Krossing
Summary: CO2 valorization is a key measure to achieve climate neutrality. Heteropoly acids are introduced as capable dehydration catalysts for direct dimethyl ether (DME) synthesis from CO2 and H-2. Thermodynamic calculations confirm that direct DME synthesis is superior to sole methanol synthesis. Experimental results show that direct DME synthesis has higher yields compared to methanol synthesis at 250 degrees Celsius.
Article
Chemistry, Multidisciplinary
Dustin Kubas, Jennifer Maria Beck, Erdogan Kasisari, Timo Schaetzler, Anita Becherer, Anna Fischer, Ingo Krossing
Summary: The direct synthesis of dimethyl ether (DME) from CO2 hydrogenation was investigated using an improved bifunctional catalyst in a fixed bed reactor. Various combinations of a methanol-producing part and a methanol dehydration part were tested, and the results showed that HPA-coated catalysts exhibited higher activity and resilience toward deactivation. Dual-grain preparation method showed superior performance over single-grain.
Review
Chemistry, Multidisciplinary
Malte Sellin, Ingo Krossing
Summary: CO is one of the most important ligands in organometallic chemistry and can form transition metal carbonyl cations (TMCCs), but their synthesis is challenging due to their high reactivity.
ACCOUNTS OF CHEMICAL RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Jan M. Rall, Max Lapersonne, Marcel Schorpp, Ingo Krossing
Summary: This article reports the synthesis and characterization of nickelocenium cations. Diamagnetic [NiCp2]2+ represents the first example of an unsubstituted parent metallocene dication. The salts were generated and characterized using various experimental methods.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Antoine Barthelemy, Harald Scherer, Michael Daub, Alexis Bugnet, Ingo Krossing
Summary: The reaction between bisdicyclohexylphosphinoethane (dcpe) and subvalent M(I) sources [M-I(PhF)(2)][pf] (M=Ga+, In+; [pf]-=[Al(ORF)(4)]-; R-F=C(CF3)(3)) resulted in the formation of salts [{M(dcpe)}(2)][pf](2), which contain the first reported dicationic, trans-bent digallene, and diindene structures. The M-I double bonds, which display a ditetrylene-like structure, are surprisingly short. Quantum chemical calculations and molecular analyses were conducted to compare the bonding situation in these salts with that in the isoelectronic and isostructural, but neutral digermenes and distannenes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Andreas Billion, Andreas Vogel, Jonas Schulte, Harald Scherer, Ingo Krossing
Summary: Oxymethylene dimethyl ethers (OMEn) are promising sustainable synthetic fuels synthesized from CO2 and green H-2. This study presents a novel continuous, anhydrous reaction setup to overcome synthetic problems and successfully synthesizes OMEn. The catalysts immobilized in ionic liquids demonstrate excellent catalytic performance and stable results in continuous operations.
Article
Chemistry, Inorganic & Nuclear
Sven Froitzheim, Jannik Junge, Christopher Barnehl, Tobias A. Engesser, Jan Krahmer, Christian Naether, Felix Tuczek
Summary: This study synthesized and characterized a series of linear tridentate ligands and molybdenum tricarbonyl complexes. The results revealed that the different phosphine donor groups in the ligands influenced the bonding and activation of CO ligands. Importantly, all complexes adopted a fac geometry, contrasting with similar complexes.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Gauthier Studer, Alexei Schmidt, Jan Buettner, Maximilian Schmidt, Anna Fischer, Ingo Krossing, Birgit Esser
Summary: This article introduces a potential rechargeable aluminum-ion battery (AIB) material with a high specific capacity. The redox polymer can act as a positive electrode material, overcoming the limitations of current AIBs. It exhibits a reversible two-electron redox process and achieves a specific capacity of up to 167 mA h g(-1), surpassing graphite as a positive electrode material. The AIB also demonstrates excellent capacity retention at fast rates and can be cycled reversibly at slower rates, making it a promising candidate for sustainable energy storage devices.
ENERGY & ENVIRONMENTAL SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Christoph Riesinger, David Roehner, Ingo Krossing, Manfred Scheer
Summary: A rational synthetic pathway was developed to synthesize a series of cyclo-P-5-bearing multi-decker complexes. By combining [Cp*Fe(mu,eta(5 : 5)-P-5)] (A) with low-valent transition metal cations, triple-decker complexes [Cp*Fe(mu,eta(5 : 5)-P-5)MCp '''][WCA] (M = Cr - Ni; WCA = weakly coordinating anion, Cp ''' = 1,2,4-(Bu3C5H2)-Bu-t) were obtained. Utilizing arene complexes [M(C6R6)(2)][WCA](n) (M = Fe, Co) allowed the synthesis of unprecedented cyclo-P-5-containing quadruple-decker complexes [{Cp*Fe(mu,eta(5 : 5)-P-5)}(2)M][pf](n) (M = Fe, Co).
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Andreas Billion, Marcel Schorpp, Rebecca Feser, Manuel Schmitt, Lea Eisele, Harald Scherer, Takaaki Sonoda, Hajimu Kawa, Burkhard Butschke, Ingo Krossing
Summary: Weakly coordinating anions (WCAs) are used to stabilize and isolate reactive cations. The alkoxyaluminate-based WCA [Al(OC(CF3)(3))(4)](-) ([pf](-)) is widely used but can still be coordinated by small cations. A novel WCA [Al(OC10F15)(4)](-) ([pfAd](-)) is more stable due to its rigid core framework. Various salts containing [pfAd](-) were synthesized and characterized by spectroscopy and crystallography. The water stability of [pfAd](-) was demonstrated by the successful synthesis of Tl[pfAd] in a mixture of solvents.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Multidisciplinary
Andreas Billion, Jonas Schulte, Andreas Vogel, Felix Hilfinger, Ingo Krossing
Summary: A novel continuous route for synthesizing oxymethylene dimethyl ethers (OMEn) by the reaction of molecular formaldehyde and dimethyl ether is presented. Acidic, porous, and thermally stable zeolites proved to be effective catalysts for this reaction. The results contribute to a better understanding of the complex reaction network in the OMEn synthesis and provide important insights for establishing an energy efficient and sustainable OMEn production process.
