@article {170, title = {A Silver-Chalcogenide Nanomaterial Enveloped with a Carborane-Thiolate Shell for the Electroreduction of CO2 to CO}, journal = {ACS Applied Nano Materials}, year = {2025}, month = {07/2025}, type = {Full article}, abstract = {

Electrocatalytic CO2 reduction using atomically precise nanomaterials has garnered significant research interest, owing to their controllable molecular structures. Here, we have synthesized an electrocatalyst composed of single crystals having a one-dimensional assembly of silver atoms bridged by sulfur atoms of meta-carborane-9-thiolates. The molecular structure of the framework was further characterized through high-resolution ESI-MS, which exhibited silver- and carborane-thiolate-containing ions originating from the fragmentation of the framework. This thermally stable solid acted as an efficient catalyst for the electrocatalytic conversion of CO2 to CO with a Faradaic efficiency of 85 {\textpm} 3\%. In situ Raman studies provided experimental verification of binding of CO2 to the framework. First-principles density functional theory calculations confirmed the feasible adsorption of CO2 with the Ag chains, highlighting its favorable interaction with the catalyst. Furthermore, free energy calculations revealed the rate-determining step of the conversion process to be the formation of *COOH. This study presents an efficient electrocatalyst featuring a one-dimensional silver-chalcogenide framework.

}, keywords = {silver chalcogenide CO2 reduction carborane thiol}, doi = {https://doi.org/10.1021/acsanm.5c01918}, url = {https://pubs.acs.org/doi/10.1021/acsanm.5c01918}, author = {Arijit Jana and Zhengyuan Li and Amoghavarsha Ramachandra Kini and Vivek Yadav and Akhil S Nair and Astrid Campos Mata and Jingjie Wu and Jan Machacek and Tomas Base and Biswarup Pathak and Soumyabrata Roy and Thalappil Pradeep} } @article {161, title = {Carborane-thiol protected copper nanoclusters: Stimuli-responsive materials with tunable phosphorescence}, journal = {Chemical Science}, volume = {14}, year = {2023}, month = {12/2023}, pages = {1613-1626}, type = {Article}, chapter = {1613}, abstract = {

Atomically precise nanomaterials with tunable solid-state luminescence attract global interest. In this work, we present a new class of thermally stable isostructural tetranuclear copper nanoclusters (NCs), shortly Cu4@oCBT, Cu4@mCBT and Cu4@ICBT, protected by nearly isomeric carborane thiols: ortho-carborane-9-thiol, meta-carborane-9-thiol and ortho-carborane 12-iodo 9-thiol, respectively. They have a square planar Cu4 core and a butterfly-shaped Cu4S4 staple, which is appended with four respective carboranes. For Cu4@ICBT, strain generated by the bulky iodine substituents on the carboranes makes the Cu4S4 staple flatter in comparison to other clusters. High-resolution electrospray ionization mass spectrometry (HR ESI-MS) and collision energy-dependent fragmentation, along with other spectroscopic and microscopic studies confirm their molecular structure. Although none of these clusters show any visible luminescence in solution, bright μs-long phosphorescence is observed in their crystalline forms. The Cu4@oCBT and Cu4@mCBT NCs are green emitting with quantum yields (Ф) of 81 and 59 \%, respectively, whereas Cu4@ICBT is orange emitting with a Φ of 18 \%. Density functional theory (DFT) calculations reveal the nature of their respective electronic transitions. The green luminescence of Cu4@oCBT and Cu4@mCBT clusters get shifted to yellow after mechanical grinding, but it is regenerated after exposure to solvent vapour, whereas the orange emission of Cu4@ICBT is not affected by mechanical grinding. Structurally flatten Cu4@ICBT didn{\textquoteright}t show mechonoresponsive luminescence in contrast to other clusters, having bent Cu4S4 structures. Cu4@oCBT and Cu4@mCBT are thermally stable up to 400 {\textdegree}C. The Cu4@oCBT retained green emission even upon heating to 200 {\textdegree}C under ambient conditions, while Cu4@mCBT changed from green to yellow in the same window. This is the first report on structurally flexible carborane thiol appended Cu4 NCs having stimuli-responsive tunable solid-state phosphorescence.

}, keywords = {boron, Cluster, Copper, Cu4L4, Phosphorescence, Responsive}, doi = {https://doi.org/10.1039/D2SC06578A}, url = {https://pubs.rsc.org/en/content/articlelanding/2023/sc/d2sc06578a}, author = {Arijit Jana and Madhuri Jash and Wakeel Ahmed Dar and Jayoti Roy and Papri Chakraborty and Paramasivam Ganesan and Sergei Lebedkin and Kaplan Kirakci and Sujan Manna and P. K. Sudhadevi Antharjanam and Jan Machacek and Monika Kucerakova and Sundargopal Ghosh and Kamil Lang and Manfred Kappes and Tomas Base and T. Pradeep} } @article {158, title = {Carboranethiol-Protected Propeller-Shaped Photoresponsive Silver Nanomolecule}, journal = {Inorganic Chemistry}, volume = {61}, year = {2022}, month = {May 27, 2022}, pages = {8593-8603}, type = {Article}, chapter = {8593}, abstract = {

We report the synthesis, structural characterization, and photophysical properties of a propeller-shaped Ag21 nano-molecule with six rotary arms, protected with m-carborane-9-thiol (MCT) and triphenylphosphine (TPP) ligands. Structural analysis reveals that the nanomolecule has an Ag13 central icosahedral core with six directly connected silver atoms and two more silver atoms connected through three Ag-S-Ag bridging motifs. While 12 MCT ligands protect the core through metal-thiolate bonds in a 3-6-3-layered fashion, two TPP ligands solely protect the two bridging silver atoms. Interestingly, the rotational orientation of a silver sulfide staple motif is opposite to the orientation of carborane ligands, resembling the existence of a bidirectional rotational orientation in the nanomolecule. Careful analysis reveals that the orientation of carborane ligands on the cluster{\textquoteright}s surface resembles an assembly of double rotors. The zero circular dichroism signal indicates its achiral nature in solution. There are multiple absorption peaks in its UV-vis absorption spectrum, characteristic of a quantized electronic structure. The spectrum appears as a fingerprint for the cluster. High-resolution electrospray ionization
mass spectrometry proves the structure and composition of the nanocluster in solution, and systematic fragmentation of the molecular ion starts with the loss of surface-bound ligands with increasing collision energy. Its multiple optical absorption features are in good agreement with the theoretically calculated spectrum. The cluster shows a narrow near-IR emission at 814 nm with a Stokes shift of 355 nm. The Ag21 nanomolecule is thermally stable at ambient conditions up to 100 {\textdegree}C. However, white-light illumination (lamp power = 120-160 W) shows photosensitivity, and this induces structural distortion, as confirmed by changes in the Raman and electronic absorption spectra. Femtosecond and nanosecond transient absorption studies reveal an exceptionally stable excited state having a lifetime of 3.26 {\textpm} 0.02 μs for the carriers, spread over a broad wavelength region of 500-650 nm. The formation of core-centered long-lived carriers in the excited state is responsible for the observed light-activated structural distortion.

}, keywords = {Ag21, boron, carborane, clusters, double rotor, luminescence, silver, thiol}, doi = {https://doi.org/10.1021/acs.inorgchem.2c00186}, url = {https://pubs.acs.org/doi/10.1021/acs.inorgchem.2c00186}, author = {Arijit Jana and Parvathy M Unnikrishnan and Ajay K Poonia and Jayoti Roy and Madhuri Jash and Ganesan Paramasivam and Jan Machacek and Kumaran Nair Valsala Devi Adarsh and Tomas Base and Thalappil Pradeep} } @article {153, title = {Icosahedral Carbaboranes with Peripheral Hydrogen{\textendash} Chalcogenide Groups: Structures from Gas Electron Diffraction and Chemical Shielding in Solution}, journal = {Chemistry A European Journal}, volume = {25}, year = {2019}, month = {February 11, 201}, pages = {2313-2321}, type = {Full paper}, chapter = {2313}, abstract = {

Hydrochalcogeno carbaboranes: Icosahedral carbaboranes with thiol and selenol groups were prepared and their structures determined by gas electron diffraction augmented by ab initio calculated data (see figure). A method for quantifying the experimental contribution to the structural parameters was developed and tested. Comparison of NMR chemical shifts in solution with quantum-chemically calculated values allowed further structural information to be retrieved.

}, keywords = {carborane-diselenol, carborane-dithiol, gass phase electron diffraction, GPE, sturcture}, doi = {DOI : 10.1002/chem.201805145}, url = {https://onlinelibrary.wiley.com/doi/10.1002/chem.201805145}, author = {Tomas Base and Josef Holub and Jindrich Fanfrlik and Drahomir Hnyk and Paul L Lane and Derek A Wann and Yury V Vishnevskiy and Denis Tikhonov and Christian G Reuter and Norbert W Mitzel} } @article {154, title = {When does a supramolecular synthon fail? Comparison of bridgehead-functionalized adamantanes: the tri- and tetra- amides and amine hydrochlorides}, journal = {Crystal Growth \& Design}, year = {2019}, month = {July 12, 2019}, type = {Full paper}, abstract = {

1,3,5-trisubstituted adamantane carboxamide and amine hydrochloride, Ad(CONH2)3 {\textperiodcentered} 2.5H2O and [Ad(NH3)3]Cl3 {\textperiodcentered} H2O (Ad = adamant-n-yl) respectively, crystallized from aqueous solutions, possess crystal structures with predictable H-bonded assembly, consistent with the C3v symmetry of the building blocks. The triamide structure consists of interpenetrated hexagonal networks, sustained by the well-known cyclic H-bonded bis-amide synthon, R22(8), which ensures linear connectivity. The structure of the triamine hydrochloride, assembled through the tetrahedral {RN+H3---(Cl-)3} synthon, features a remarkably symmetric assembly with narrow trigonal pore-channels, hosting water molecules. The structures of the tetrahedral 1,3,5,7-tetrasubstituted Ad(CONH2)4 and [Ad(NH3)4]Cl4, obtained similarly, demonstrate a formal prediction failure of synthon based approach. Instead of the anticipated bis-amide synthon based diamond network (1.485 g cm-3) analogous to the 5-fold interpenetrated paradigmatic structure of Ad(COOH)4, a non-interpenetrated assembly, sustained by a dense network of H-bonds, is realized (1.433 g cm-3). Lessened geometric regularity was also found in the tetrahydrochloride salt assembled via 5-connected nodes, {RN+H3---(Cl-)4}, which involve a bifurcated H-bond. The failures of the supramolecular synthons in these simple cases could be interpreted either in terms of symmetry and/or limitations associated with the {\textquoteleft}synthon-density{\textquoteright}. A potential machine learning approach oriented on heuristic retrosupramolecular synthesis relies on such selected high-weight conceptual cases.

}, keywords = {adamantane, amide, amine, crystal structure, H-bond, hydrochloride, prediction, supramolecular synthon, violation}, doi = {https://doi.org/10.1021/acs.cgd.9b00594}, url = {https://pubs.acs.org/doi/10.1021/acs.cgd.9b00594}, author = {Ishtvan Boldog and Guido Reiss and Kostiantyn V. Domasevitch and Tomas Base and Stefan Braese} } @article {138, title = {The gaseous structure of closo-9,12-(SH)2-1,2-C2B10H10, a modifier of gold surfaces, as determined using electron diffraction and computational methods}, journal = {Dalton Transactions}, volume = {42}, year = {2013}, chapter = {12015}, abstract = {

The molecular structure of closo-9,12-(SH)2-1,2-C2B10H10 has been determined by the concerted use of quantum chemical calculations and gas electron diffraction (GED). For the purposes of GED, the architecture of the carbaborane cage was simplified to allow it to have C2v symmetry, while the positioning of the thiol groups means that the molecule had overall C1 symmetry. The accuracy of the experimental structure, as well as that calculated at the MP2(full)/6-311++G(3df,3pd) level, has been gauged by comparison of experimental 11B NMR chemical shifts with those calculated using gauge-invariant atomic orbitals (GIAO) methods. The inclusion of electron correlation in the magnetic property calculations (GIAO-MP2) gave superior results to those carried out using GIAO-HF. The electronic structure of this derivative, with respect to its directional interaction with a metal surface, is outlined.

}, doi = {10.1039/c3dt51393a}, url = {http://pubs.rsc.org/en/results?artrefjournalname=dalton\%20trans.\&artrefstartpage=12015\&artrefvolumeyear=2013\&fcategory=journal}, author = {Derek A Wann and Paul D Lane and Heather E Robertson and Tomas Base and Drahomir Hnyk} } @article {120, title = {Carbon-substituted 9,12-dimercapto-1,2-dicarba-closo-dodecaboranes via a 9,12-bis(methoxy-methylthio)-1,2-dicarba-closo-dodecaborane precursor}, journal = {Polyhedron}, volume = {45}, year = {2012}, chapter = {144}, doi = {10.1016/j.poly.2012.07.067}, url = {http://www.sciencedirect.com/science/article/pii/S0277538712005207}, author = {Jens Langecker and Karla Fejfarova and Michal Dusek and Daniel Rentsch and Tomas Base} } @article {119, title = {Decaborane Thiols as Building Blocks for Self-Assembled Monolayers on Metal Surfaces}, journal = {Inorganic Chemistry}, volume = {51}, year = {2012}, chapter = {1685}, abstract = {

Three nido-decaborane thiol cluster compounds, [1-(HS)-nido-B10H13] 1, [2-(HS)-nido-B10H13] 2, and [1,2-(HS)2-nido-B10H12] 3 have been characterized using NMR spectroscopy, single-crystal X-ray diffraction analysis, and quantum-chemical calculations. In the solid state, 1, 2, and 3 feature weak intermolecular hydrogen bonding between the sulfur atom and the relatively positive bridging hydrogen atoms on the open face of an adjacent cluster. Density functional theory (DFT) calculations show that the value of the interaction energy is approximately proportional to the number of hydrogen atoms involved in the interaction and that these values are consistent with a related bridging-hydrogen atom interaction calculated for a B18H22 C6H6 solvate. Self-assembled monolayers (SAMs) of 1, 2, and 3 on gold and silver surfaces have been prepared and characterized using X-ray photoelectron spectroscopy. The variations in the measured sulfur binding energies, as thiolates on the surface, correlate with the (CC2) calculated atomic charge for the relevant boron vertices and for the associated sulfur substituents for the parent B10H13(SH) compounds. The calculated charges also correlate with the measured and DFT-calculated thiol 1H chemical shifts. Wetting-angle measurements indicate that the hydrophilic open face of the cluster is directed upward from the substrate surface, allowing the bridging hydrogen atoms to exhibit a similar reactivity to that of the bulk compound. Thus, [PtMe2(PMe2Ph)2] reacts with the exposed and acidic B }, doi = {10.1021/ic202000b}, author = {Jonathan Bould and Jan Machacek and Michael G S Londesborough and Ramon Macias and John D Kennedy and Zdenek Bastl and Patrik Rupper and Tomas Base} } @article {118, title = {Tuning the surface potential of Ag surfaces by chemisorption of oppositely-oriented thiolated carborane dipoles}, journal = {Journal of Colloid and Interface Science}, volume = {354}, year = {2011}, chapter = {168}, abstract = {

Two selected carboranethiol isomers were used to modify flat silver surfaces. Both isomers, 1,2-(HS)2 }, doi = {10.1016/j.jcis.2010.10.052}, url = {http://www.sciencedirect.com/science/article/pii/S0021979710012385}, author = {Jorn F Lubben and Tomas Base and Patrick Rupper and Tina Kunniger and Jan Machacek and Sebastien Guimond} } @article {160, title = {Carborane-thiol protected copper nanoclusters: Stimuli-responsive materials with tunable phosphorescence }, journal = {Chemical Science}, abstract = {

Atomically precise nanomaterials with tunable solid-state luminescence attract global interest. In this work, we present a new class of thermally stable isostructural tetranuclear copper nanoclusters (NCs), shortly Cu4@oCBT, Cu4@mCBT and Cu4@ICBT, protected by nearly isomeric carborane thiols: ortho-carborane-9-thiol, meta-carborane-9-thiol and ortho-carborane 12-iodo 9-thiol, respectively. They have a square planar Cu4 core and a butterfly-shaped Cu4S4 staple, which is appended with four respective carboranes. For Cu4@ICBT, strain generated by the bulky iodine substituents on the carboranes makes the Cu4S4 staple flatter in comparison to other clusters. High-resolution electrospray ionization mass spectrometry (HR ESI-MS) and collision energy-dependent fragmentation, along with other spectroscopic and microscopic studies confirm their molecular structure. Although none of these clusters show any visible luminescence in solution, bright μs-long phosphorescence is observed in their crystalline forms. The Cu4@oCBT and Cu4@mCBT NCs are green emitting with quantum yields (Ф) of 81 and 59 \%, respectively, whereas Cu4@ICBT is orange emitting with a Φ of 18 \%. Density functional theory (DFT) calculations reveal the nature of their respective electronic transitions. The green luminescence of Cu4@oCBT and Cu4@mCBT clusters get shifted to yellow after mechanical grinding, but it is regenerated after exposure to solvent vapour, whereas the orange emission of Cu4@ICBT is not affected by mechanical grinding. Structurally flatten Cu4@ICBT didn{\textquoteright}t show mechonoresponsive luminescence in contrast to other clusters, having bent Cu4S4 structures. Cu4@oCBT and Cu4@mCBT are thermally stable up to 400 {\textdegree}C. The Cu4@oCBT retained green emission even upon heating to 200 {\textdegree}C under ambient conditions, while Cu4@mCBT changed from green to yellow in the same window. This is the first report on structurally flexible carborane thiol appended Cu4 NCs having stimuli-responsive tunable solid-state phosphorescence.

}, keywords = {boron, carborane, Cluster, Copper, Phosphorescence, Responsive, thiol}, doi = {https://doi.org/10.1039/D2SC06578A}, url = {https://pubs.rsc.org/en/content/articlelanding/2023/sc/d2sc06578a}, author = {Arijit Jana and Madhuri Jash and Wakeel A Dar and Jayoti Roy and Papri Chakraborty and Paramasivam Ganesan and Sergei Lebedkin and Kaplan Kirakci and Sujan Manna and P. K. Sudhadevi Antharjanam and Jan Machacek and Monika Kucerakova and Sundargopal Ghosh and Kamil Lang and Manfred Kappes and Tomas Base and T. Pradeep} }