bluuebunny/crossref_metadata_2025_split huggingface dataset:
(Invited) 3D Aromaticity in Borane and Carborane Derivatives
Authors: Solà Miquel , Poater Jordi , Tu Deshuang , Yan Hong , Viñas Clara , Teixidor Francesc 
Published: September 2023

We will start discussing the difference between 3D aromatic species and those that should be described as 2D-aromatic with three-dimensional molecular structures (abbr. 2D-aromatic-in-3D) and not as truly 3D-aromatic [1]. Then, we will show the connection between archetypal polycyclic aromatic hydrocarbons (PAH) and closo boranes to conclude that the 4n+2 Wade-Mingos rule for three-dimensional closo boranes is connected to the (4n+2)π Hückel rule for bidimensional PAHs [2]. Next, we will analyze the aromaticity of closo and nido boranes and carboranes. Quantum chemical calculations reveal that the nido cage retains part of the aromatic character that characterizes the closo borane cages [2]. Then, we will elaborate on the aromaticity in benzenoids (2D aromatic) linked to carboranes (3D aromatic) [3]. And finally, we will apply the Clar’s π-sextet model to explain the extrusion of benzenoids linked to cobaltabis(dicarbollide), [3,3’-Co(1,2-C2B9H11)2]- [4].

References

1) El Bakouri, O.; Szczepanik, D. W.; Jorner, K.; Ayub, R.; Bultinck, P.; Solà, M.; Ottosson, H. J. Am. Chem. Soc.
2022, 144, 8560-8575
2) a) Poater, J.; Solà, M.; Viñas, C.; Teixidor, F. Angew.
Chem. Int. Ed.
2014, 53, 12191-12195. b) Poater, J.; Solà, M.; Viñas, C.; Teixidor, F. Chem. Eur. J.
2016, 22, 7437-7443.
3) a) Poater, J.; Viñas, C.; Solà, M.; Teixidor, F. Nat.
Commun.
2022, 13, 3844. b) Sun, F.; Tan, S.; Lu, C.; Tu, D.; Poater, J.; Solà, M.; Yan, H.; submitted for publication.
4) Poater, J.; Viñas, C.; Olid, D.; Solà, M.; Teixidor, F. Angew.
Chem. Int. Ed.
2022, 61, e202200672.

Figure 1
(Invited) On-Surface Synthesis of Π-Conjugated Polymers
Authors: Ecija David 
Published: September 2023

On-surface synthesis has emerged as a powerful strategy to design unprecedented nanomaterials. In this talk, I will revise our recent achievements regarding the synthesis of one-dimensional π-conjugated polymers, featuring emerging physical properties such as non-trivial topology or pi-based magnetism.1-6

References
[1] Advanced Materials 33, 2170349, 2021
[2] Angewandte Chemie International Edition 59, 17594-17599, 2020
[3] Nature communications 11, 1-8, 2020
[4] Nature Nanotechnology 15, 437-443, 2020
[5] Chemical Communications 56, 15309-15312, 2021
[6] Angewandte Chemie International Edition 58, 6781-6781, 2019
(Invited) Anisotropic Contributions in the Chromatographic Elution Behavior of Fullerenes and Fullertubes
Authors: Bourret Emmanuel , Côté Michel , Stevenson Steven 
Published: September 2023

Since their discovery in the mid-1980s, the fullerenes have been confined to molecules of less than 100 atoms. With the recent development of a method allowing the isolation of pristine samples[1], the discovery of increasingly long fullertubes, hybrid between a fullerene and a nanotube, is stimulating renewed interest in the field of fullerene science. The increase in the number of atoms comes at a price, the explosion in the number of possible isomers, among which we must identify the experimentally isolated structure. Fuch’s model[2] is commonly used to explain the interaction between fullerenes and non-polar HPLC columns. Still, this approach cannot always differentiate between isomers as the results depend only on the average polarizability, which varies little for fullerenes with the same number of carbon atoms.
In this presentation, we will discuss the use of polarizability anisotropy to differentiate isomers in the context of chromatographic elution. It allows us to generalize Fuchs’ model by adding anisotropic contributions leading to a finer description of fullerenes elution behavior and a better isomeric identification.
[1] R.M. Koenig, H.-R. Tian, T.L. Seeler, K.R. Tepper, H.M. Franklin, Z.-C. Chen, S.-Y. Xie, and S. Stevenson, J. Am. Chem. Soc. 142, 15614 (2020).
[2] D. Fuchs, H. Rietschel, R.H. Michel, A. Fischer, P. Weis, and M.M. Kappes, J. Phys. Chem. 100, 725 (1996).

Figure 1
(Invited) Conducting the Scholl Reaction: Spironanographenes Vs Helically Arranged Nanographenes
Authors: Izquierdo-García Patricia , Fernández-García Jesús Manuel , Martín Nazario 
Published: September 2023

The stepwise synthesis of graphene molecular fragments, molecular nanographenes (NGs), allows the design and monodisperse preparation of sophisticated molecules with perfectly defined shapes and properties.1 The introduction of defects to the honeycomb pattern allows the preparation of nanographenes with finely tunable characteristics, as chirality. Helicenes and non-hexagonal rings are the most usual motifs to this end, as they generate axial chirality by diverting the structures from the 2D plane.
In 2021 we reported a new family of molecular nanographenes in which the axial chirality results from the helical arrangement of the graphitized moieties covalently connected through a tetrafluorobenzene core 1.2 Although two enantiomers were confirmed by x-ray diffraction and chiral HPLC, racemization was observed.3 The isomerization process was evaluated, and the isomerization barrier resulted of ∆G≠= 24.6 kcal/mol at 40 ºC, which corresponds to a half-life time of t½ = 107 min.
In order to modulate both optoelectronic and chiroptical properties we decided to increase the rigidity of the structure by introducing a 9,10-anthracene as central core. However, unexpected spironanographene 2 was obtained during the key step in the synthesis of nanographenes, the Scholl reaction. Under different reaction conditions we were able to obtain spirocompounds with different graphitization degree. Herein we reported the first spirocycles formation under Scholl reaction conditions without interrupting the graphitization process.4 To further understand the formation of the unexpected nanographenes, theoretical calculations were carried out and revealed the formation of a trityl cation that is involved in the formation of the spirocycles.
Furthermore, in order to conduct the reaction towards the formation of the expected rigid helically arranged nanographene, an electron deficient core was designed. The substitution of the central anthracene with eight electron withdrawing fluorine atoms destabilizes the trityl cation and the expected helically arranged nanographene 3 was obtained.4

[1] Y. Gu, K. Müllen. J. Am.
Chem. Soc.
2022
, 144, 11499–11524.
[2] P. Izquierdo-García, J. M. Fernández-García, I. Fernández, J. Perles, N. Martín. J. Am. Chem. Soc. 2021, 143, 11864–11870.
[3] J. M. Fernández-García, P. Izquierdo-García, M. Buendía, S. Filippone and N. Martín. Chem. Commun. 2022, 58, 2634-2645.
[4] P. Izquierdo-García, J. M. Fernández-García, J. Perles, I. Fernández, N. Martín. Manuscript in preparation.

Figure 1
(Invited) Fullerenes in Water: The Formation of Hydrogels
Authors: Porfyrakis Kyriakos 
Published: September 2023

Hydrogels are emerging as important materials to achieve medical advances, in applications such as cellular scaffoldings in regenerative medicine/tissue engineering, tissue replacements, wound dressings, and drug/gene/protein/RNA delivery systems among others. This is due to their high-water content and their similarities to the structural form of living tissues. Hydrogels are most useful when they can be compatible with the dynamics of healthy tissues, while at the same time they are able to deliver therapeutic molecules at specified locations.
In this talk, I will present our recent work in using fullerenes and their derivatives for biomedical engineering. Fullerenes are attractive for a number of reasons: their surface can be functionalised to enhance their biocompatibility and water solubility; they can encapsulate molecules in endohedral form, and they have shown antiviral, antibacterial and antioxidant activity. The physical properties of fullerenes make them ideal candidates to produce supramolecular structures and hydrogels without the need for an external polymeric matrix. I will show the synthesis of supramolecular hydrogels solely from covalently-functionalised C60. I will also demonstrate the synthesis of new kinds of supramolecular hydrogels made from fullerenes of different sizes (C60, C84 and C90–92) functionalised with hydrophilic oligoethylene glycol chains. Carrying out the reaction on fullerenes of different sizes, including C70, allows us to interrogate the effect of fullerene shape on chemical functionalization, and thus, self-assembly behaviour.
We believe these fullerene hydrogels may have biomedical applications. Furthermore, they maybe sought after for electrochemical applications such as next-generation capacitors.
DNA Linked Mixed-Dimensional Heterostructures: The Designing, Nanoscale Control and Device Applications of Tmdc-Quantum Dot Nanohybrids
Authors: Chen Kai , Talha-Dean Teymour , Zheng Tingting , Dimitrov Stoichko , Mol Jan , Palma Matteo 
Published: September 2023

DNA Linked Mixed-Dimensional Heterostructures: the Designing, Nanoscale Control and Device Applications of TMDC-Quantum Dot Nanohybrids

Kai Chen,a Teymour Talha-Dean,b Tingting Zheng, a Stoichko Dimitrov, a Jan Mol b and Matteo Palma a

aDepartment of chemistry, Queen Mary University of London, London E1 4NS, United Kingdom

bDepartment of Physics, Queen Mary University of London, London E1 4NS, United Kingdom
The construction of mixed-dimensional heterostructures is a promising approach for the development of biosensing and optoelectronic systems and devices. The accurate nanoscale control of the heterostructures interface is a key challenge, for instance to tune the distance between the individual components and their stoichiometry, that in turn affect their electronic coupling. In this regard, DNA can be a powerful structural and functional linker for nano-hybrids assembly, due to its tunability down to sub-nanometer control.
Our current interest is focused on the fabrication of TMDC-based nanohybrids using double stranded (ds) DNA as both a linker and templating moiety. In particular, we recently employed three different approaches to functionalize the surface of MoS2 nanoflakes and assembled 0D (quantum dots)/2D (MoS2 flakes) hybrids using DNA as a connection moiety (see figure).[1] DNA allowed us to control the distance between QDs and MoS2 with sub-nanoscale accuracy, allowing the fine tuning of the electronic coupling between the two nanostructures.
We will further discuss the construction of mixed-dimensional nanohybrids i) via the use different DNA nanotechnology strategies, and ii) for the fabrication of responsive optoelectronic devices.
[1] T. Talha-Deam, K. Chen, G. Mastroianni, F. Gesuele, J. Mol and M. Pamla. “Nanoscale Control of DNA-Linked MoS2-Quantum Dot Heterostructures”. Bioconjugate Chemistry, 2022, DOI: 10.1021/acs.bioconjchem.2c00285
(Invited) Unraveling Electron-Phonon Coupling in 2D Materials in Momentum and Time with Ultrafast Electron Diffuse Scattering (UEDS)
Authors: Siwick Bradley John 
Published: September 2023

The nature of the couplings within and between lattice and charge degrees of freedom is central to an understanding of electrical and heat transport in materials. These interactions are essential to phenomena as diverse as superconductivity, charge density waves and carrier mobility in semiconductors and metals. Despite their fundamental role, detailed momentum-dependent information on the strength of electron-phonon coupling (EPC) and phonon-phonon coupling (PPC) across the entire Brillouin zone has proved to be very difficult to obtain.
I will describe an emerging pump-probe technique, ultrafast electron diffuse scattering (UEDS), that provides such information from the perspective of the phonon system directly. Recent examples of the application of UEDS to layered (2D) materials will be the focus. First, in the thermoelectric material SnSe – a strongly polar semiconductor – we directly observe the phonon dressing processes that yield carrier localization and polaron formation with UEDS. In SnSe these phonon dressing dynamics are profoundly bimodal, with the fast (300 fs) process associated with the formation of a quasi-1D lattice distortion and a relatively large polaron and the slower (4 ps, an order of magnitude slower timescale) process associated with small polaron formation. The observations in SnSe are consistent with electron and hole polarons being different sizes, or the process of polaron formation being instrincially bimodal for both carriers in a manner reminiscent of Lars Onsager’s inverse snowball effect. Second, the extension of UEDS to a MoS2 monolayer heterostructure will be demonstrated. These results reveal substrate dielectric screening of the electron-phonon interaction within the monolayer as well as the monomentum-dependent carrier-phonon equilibration. These results are compared directly against ab-initio simulations of these processes

Figure 1
Advanced Characterization by Using Coupled Operando Mass Spectrometry and Operando Dilatometry
Authors: Petit Jan , Heugel Philipp , Joos Martin , Klein Franziska , Tübke Jens 
Published: September 2023

Mechanical modifications or harmful side reactions are undesirable ageing effects that can occur during cycling. These phenomena have a negative impact on cell performance and consequently limit cycle life. The focus here is on investigations of ageing processes such as volume changes and electrolyte decomposition during cycling.
Combined thickness measurements and gas analytical studies of Li-Graphite half cells with a carbonate-based electrolyte are presented. In addition, the same measurements on Li-O2 cells with an ether-based electrolyte are introduced. The electrolytes consist of 1M LiPF6 in EC:DMC (1:1, wt) and 1M LiTFSI in DEGDME, respectively. All measurements were carried out using specially developed multifunctional test setups and accordingly modified test cells. The different cell specifications were examined by operando mass spectrometry (MS) and operando dilatometry. In addition, post-mortem gas chromatography-mass spectrometry (GC-MS) was conducted.
Application-oriented analysis such as gas analysis, thickness measurements or both combined are suitable methods to define operating parameter, to benchmark and to identify decomposition reactions. Operando electrochemical dilatometry was conducted to check whether an irreversible increase in thickness occurred. On the corresponding cell configurations, the dilatation was recorded over the entire electrode stack as well as of the separate working electrode only. Furthermore, operando MS can be used to detect gaseous substances produced by (electro)chemical processes as a function of the state of charge. With the GC-MS, a post-mortem analysis was performed to identify the individual substances qualitatively.
Results of the different cell specifications are shown and can be compared with each other. A detailed relationship can be demonstrated between the change in thickness and the potential profile. Moreover, the cyclic formation of several degradation products is detected. Possible correlations between gas evolution and thickness changes can be shown.
In conclusion, these analytical studies provide a new important contribution to get a more detailed insight into ageing processes that take place. The possible coupling of two operando techniques enables an even more holistic examination to analyze cell performance.
Parts of the presented work are supported by the Fraunhofer and Max-Planck cooperation program in the project “Clusterbatt” together with Fraunhofer IWS, Dresden and MPIKG, Potsdam. Parts of the presented work are funded by the German Federal Ministry of Education and Research (BMBF) in the joint German-Japanese project “OsabanPlus” (03XP0469C) together with Justus-Liebig-University Giessen, TU Braunschweig and University of Kyoto.

Figure 1
Thermal Degradation of Polycrystalline Ni-Rich Cathodes, New Insights from Total Scattering and Machine-Learning Assisted Tomography
Authors: Hou Dong , Xiao Xianghui , LIU Jue , Zhou Xiao-Dong , Yang Zhijie , Xu Zhengrui , Lin Feng 
Published: September 2023

Alkali metal-based batteries (e.g., lithium batteries) are considered the most effective energy storage candidate for portable electronics, power grids, and electric vehicles due to their considerable energy density, power density, cycle life, safety, and competitive prices. The Ni-rich Co-less ternary LiNi
x
Mn
y
Co1-x-y
O2 (NMC) (Ni>80%) is one of the candidate materials due to its high discharge capacity (>200 mAh g-1) and high energy density (>750 Wh kg-1). However, the thermal stability of charged Ni-rich NMCs is inferior, following a general negative correlation between Ni content and stability. Such severer degradation in Ni-rich NMCs might lead to dysfunctionality, thermal runaway, and eventually catastrophic failure and explosion of batteries, raising enormous safety concerns. Therefore, it is critical to understand the thermal behavior of charged Ni-rich NMC cathode from different perspectives in order to conduct material design for better thermal stability.
After literature survey of typical and widely used probes by this community (e.g., diffraction, spectroscopy, imaging), we found these approaches subject to compromise to some degree in the experimental design, resulting in an inadequate description of the thermal degradation mechanism. Here we offer two novel approaches, neutron total scattering and energy-resolved 3D nano-tomography, to probe the reaction and evolution of the charged NMCs under non-ambient conditions in real-time. Such in situ measurements were only accomplished by deliberate experimental design at beamlines and deep integrations of neutron or synchrotron facilities with battery science. In situ heating neutron scattering captures the transition of crystal structure in reciprocal space (by Rietveld refinements), as well as of the local atomic framework in real space (by pair distribution function analysis). Moreover, machine learning algorithms were applied to the 3D nano-tomography datasets to reveal the detailed microstructural and oxidation state progression inside the charged particles. Thereafter, we discussed the key factors which have previously been overlooked by the community and offer constructive suggestions on particle design for thermally stable cathodes from our unique perspective.
The work was supported by the National Science Foundation under Grant no. DMR-1832613 (F.L.). The machine-learning assisted tomography analysis was partially supported from NASA under 80NSSC21M0333 and NSF under NSF-2119688 (X.-D.Z)
(Invited) Structural and Dynamics Analysis of Organic Semiconducting Materials by Solid State NMR
Authors: Suzuki Katsuaki , Kaji Hironori 
Published: September 2023

Recently, our group have successfully developed several blue and green thermally activated delayed fluorescence (TADF) emitters showing high external quantum efficiencies in OLEDs through high-throughput screening based on quantum chemical calculations. Although the conformation, aggregated structure and dynamics of TADF emitters in amorphous states is expected to be the origin of reverse intersystem crossing and resulting high device performance, the experimental approach toward these information is still limited because typical diffraction technique cannot be used to amorphous materials due to the lack of long-range order. Thus we have carried out multiscale simulations and solid-state NMR (ssNMR) analysis of organic amorphous thin films. The ssNMR is one of the powerful technique to obtain the structural and dynamics information of amorphous aggregated materials. In this presentation, we demonstrate structural and dynamics analysis of amorphous organic semiconducting materials using ssNMR.
Reference
(1) “Analysis of Molecular Orientation in Organic Semiconducting Thin Films Using Static Dynamic Nuclear Polarization Enhanced Solid-State NMR Spectroscopy”, Suzuki, K.; Kubo, S.; Aussenac, F.; Engelke, F.; Fukushima, T.; Kaji, H. Angew. Chem. Int. Ed. 2017, 56, 14842.
(2) “Efficient blue thermally activated delayed fluorescence emitters showing very fast reverse intersystem crossing”, Ren, Y., Wada, Y., Suzuki, K., Kusakabe, Y., Geldsetzer, J. and Kaji, H.

Appl. Phys. Express, 2021, 14, 071003.
(3) “Solution-processable thermally activated delayed fluorescence emitters for application in organic light emitting diodes”, Suzuki, K.; Adachi, C.; Kaji, H. J. Soc. Inf. Disp.
2017, 25, 480.
(4) “Imidazole Acceptor for Both Vacuum-Processable and Solution-Processable Efficient Blue Thermally Activated Delayed Fluorescence”, Kusakabe, Y.; Wada, Y.; Misono, T.; Suzuki, K.; Shizu, K.; Kaji, H

ACS Omega, 7, 16740 - 16745 (2022).
(5) “Triarylboron-based Fluorescent Organic Light-emitting Diodes with External Quantum Efficiencies Exceeding 20%”, Suzuki, K.; Kubo, S.; Shizu, K.; Fukushima, T.; Wakamiya, A.; Murata, Y.; Adachi, C.; Kaji, H.; Angew. Chem. Int. Ed. 2015, 54, 15231.
(5) “Purely organic electroluminescent material realizing 100% conversion from electricity to light”, Kaji, H.; Suzuki, H.; Fukushima, T.; Shizu, K.; Suzuki, K.; Kubo, S.; Komino, T.; Oiwa, H.; Suzuki, F.; Wakamiya, A.; Murata, Y.; Adachi, C. Nat. Commun. 2015, 6, 8476.
(Invited) Synthesis of Multi-Metallic Nanocatalysts Using a Dendrimer Reactor
Authors: Yamamoto Kimihisa 
Published: September 2023

Dendrimers are highly branched organic macromolecules with successive layers or “generations” of branch units surrounding a central core. Organic inorganic hybrid versions have also been produced, by trapping metal ions or metal clusters within the voids of the dendrimers. Their unusual, tree-like topology endows these nanometer-sized macromolecules with a gradient in branch density from the interior to the exterior, which can be exploited to direct the transfer of charge and energy from the dendrimer periphery to its core.
We show that AuCl3, SnCl2, FeCl3, and so on complexes to the imines groups of a spherical polyphenylazomethine dendrimer in a stepwise fashion according to an electron gradient, with complexation in a more peripheral generation proceeding only after complexation in generations closer to the core has been completed. By attaching an electron-withdrawing group to the dendrimer core, we are able to change the complexation pattern, so that the core imines are complexed last. By further extending this strategy, it should be possible to control the number and location of metal ions incorporated into dendrimer structures, which might and uses as tailored catalysts, building blocks, or fine-controlled clusters for advanced materials. The metal-assembly in a discrete dendrimer molecule can be converted to a size-regulated metal particle with a size smaller than 1 nm as a molecular reactor(Fig.). Due to the well-defined number of metal clusters in the subnanometer region, its property is much different from that of bulk or general metal nanoparticles. The chemistry of nanocatalysts on the sub-nanometer scale is not yet well understood because precise multi-metallic nanoparticles are difficult to synthesize with control over size and composition. The template synthesis of multi-metallic sub-nanocalaysts is achieved using a phenylazomethine dendrimer as a macromolecular template.

Figure 1