Conflicting Aromaticity in Trirhodium(I) Rosarin.

Aromaticity is one of the most important and widely used concepts in chemistry. Among the various experimentally discovered and theoretically predicted compounds that possess different types of aromaticity, conflicting aromaticity, where aromatic and antiaromatic electron delocalization is present in one molecule simultaneously, remains one of the most controversial and elusive concepts, although theoretically predicted 15 years ago. In this work, we synthesized a novel conflicting aromatic trirhodium complex that contains a σ-aromatic metal fragment surrounded by the π-antiaromatic organic ligand and characterized it by nuclear magnetic resonance spectroscopy, high-resolution mass spectrometry, and X-ray single crystal structure analysis.

Searching for stable copper borozene complexes in CuB and CuB.

Copper has been shown to be an important substrate for the growth of borophenes. Copper-boron binary clusters are ideal platforms to study the interactions between copper and boron, which may provide insight about the underlying growth mechanisms of borophene on copper substrates. Here we report a joint photoelectron spectroscopy and theoretical study on two copper-doped boron clusters, CuB and CuB.

Design and Implementation of a Hardware and Software System for Visual Assessment of Bituminous Coating Quality.

Typically, the quality of the bitumen adhesion in asphalt mixtures is assessed manually by a group of experts who assign subjective ratings to the thickness of the residual bitumen coating on the gravel samples. To automate this process, we propose a hardware and software system for visual assessment of bituminous coating quality, which provides the results both in the form of a discrete estimate compatible with the expert one, and in a more general percentage for a set of samples. The developed methodology ensures static conditions of image capturing, insensitive to external circumstances.

Bismuth Infrared Star: Being at a Glance.

Bismuth polycations have garnered significant attention from researchers due to their extraordinary and counter-intuitive structures and stoichiometries. Despite extensive experimental and theoretical investigations, understanding of the bonding in such clusters remains insufficient. An AdNDP bonding analysis was conducted to elucidate the bonding characteristics using both homoatomic and heteroatomic bismuth clusters with various stoichiometries.

Neural network atomistic potentials for global energy minima search in carbon clusters.

The global energy optimization problem is an acute and important problem in chemistry. It is crucial to know the geometry of the lowest energy isomer (global minimum, GM) of a given compound for the evaluation of its chemical and physical properties. This problem is especially relevant for atomic clusters.

Global Minimum Search and Bonding Analysis of Tl H and Tl H (x=0-6; y=0-5) Series.

A remarkable distinction between boron and carbon hydrides lies in their extremely different bonding patterns and chemical reactivity, resulting in diverse areas of application. Particularly, carbon, characterized by classical two-center - two-electron bonds, gives rise to organic chemistry. In contrast, boron forms numerous exotic and non-intuitive compounds collectively called non-classical structures.

Analysis of the Ability of CHI to Phosphoresce.

The heavy atom effect is a widely utilized strategy to enhance the phosphorescence intensity of organic molecules. Among the preferred choices, heavy halogen atoms such as bromine (Br) or iodine (I) have gained popularity. However, the incorporation of these heavy atoms can introduce challenges due to the presence of unstable excited states that undergo dissociation upon excitation.

Photoelectron Spectroscopy and Theoretical Study of Di-Copper-Boron Clusters: CuB and CuB.

Copper has been found to be able to mediate the formation of bilayer borophenes. Copper-boron binary clusters are ideal model systems to probe the copper-boron interactions, which are essential to understand the growth mechanisms of borophenes on copper substrates. Here, we report a joint photoelectron spectroscopy and theoretical study on two di-copper-doped boron clusters: CuB and CuB.

On the existence of CO microsolvated clusters: a theoretical study.

Microsolvated clusters of multiply charged anions play a crucial role in atmospheric chemistry and some of them were previously registered experimentally. At the same time, there are no experimental observations of [CO·(HO)]. The reasons for this may be related to the thermodynamical or kinetical instability of microsolvated CO toward autoionization or autoprotonation processes.

Exploring the Structure and Bonding of Group 13 Homogeneous and Heterogeneous Hydrides with the XH Stoichiometry: A Theoretical Investigation.

We investigated the structure evolution of the Group 13 hydrides on the example of XH (X = B, Al, Ga, In, Tl) and BAlH, AlGaH, GaInH, and InTlH stoichiometries via density functional theory (DFT) and ab initio quantum chemistry methods performing Coalescence Kick (CK) global minimum search and AdNDP chemical bonding analysis. We found that all global minimum structures possess multicenter electron bonds. The difference between the structures of XH stoichiometry for boron and aluminum is much more significant than that between other pairs of Al-Ga, Ga-In, and In-Tl.

Extending machine learning beyond interatomic potentials for predicting molecular properties.

Machine learning (ML) is becoming a method of choice for modelling complex chemical processes and materials. ML provides a surrogate model trained on a reference dataset that can be used to establish a relationship between a molecular structure and its chemical properties. This Review highlights developments in the use of ML to evaluate chemical properties such as partial atomic charges, dipole moments, spin and electron densities, and chemical bonding, as well as to obtain a reduced quantum-mechanical description.

Theoretical Investigation of Geometries and Bonding of Indium Hydrides in the InH and InH (x = 0-4,6; y = 0-5) Series.

Boron hydrides have been an object of intensive theoretical and experimental investigation for many decades due to their unusual and somewhat unique bonding patterns. Despite boron being a neighboring element to carbon, boron hydrides almost always form non-classical structures with multi-center bonds. However, we expect indium to form its interesting molecules with non-classical patterns, though such molecules still need to be extensively studied theoretically.

Tinning the carbon: hydrostannanes strike back.

Carbon possesses an important ability to be in a valence state of IV, which is essential for organic chemistry and all carbon-based life forms. In turn, tin is usually observed in the valence state of II, although it is a carbon group element. This creates an open question about the possibility of the existence of tin-based "organic" molecules.

Sn: a 2.7 nm naked aromatic tin rod.

In this work, we synthesize naked tin cluster anion Sn, representing the first example of pure Sn nanowire assembled through oxidative coupling reactions of a super atomic cluster Sn. Theoretical analysis confirm the presence of aromaticity for each Sn unit showing four adjacent aromatic subunits bridged by parallel Sn-Sn bonds.

Superalkali Coated Rydberg Molecules.

A series of complexes of Na, K, NH, and HO with [bpy.bpy.bpy]cryptand, [2.

Symmetry collapse due to the presence of multiple local aromaticity in Ge.

Understanding the structural changes taking place during the assembly of single atoms leading to the formation of atomic clusters and bulk materials remains challenging. The isolation and theoretical characterization of medium-sized clusters can shed light on the processes that occur during the transition to a solid-state structure. In this work, we synthesize and isolate a continuous 24-atom cluster Ge, which is characterized by X-ray diffraction analysis and Energy-dispersive X-ray spectroscopy, showing an elongated structural characteristic.

Overlapping electron density and the global delocalization of π-aromatic fragments as the reason of conductivity of the biphenylene network.

Recently fabricated 2D biphenylene network is an astonishing solid-state material, which possesses unique metal-like conductive properties. At the same time, two-dimensional boron nitride network (2D-BN)-an isoelectronic and structural analogue of biphenylene network, is an insulator with a wide direct bandgap. This study investigates the relationship between the electronic properties and chemical bonding patterns for these species.

Occurrence of Double Bond in -Aromatic Rings: An Easy Way to Design Doubly Aromatic Carbon-Metal Structures.

A chemical bonding of several metallabenzenes and metallabenzynes was studied via an adaptive natural density partitioning (AdNDP) algorithm and the induced magnetic field analysis. A unique chemical bonding pattern was discovered where the M=C (M: Os, Re) double bond coexists with the delocalized 6c-2e π-bonding elements responsible for aromatic properties of the investigated complexes. In opposition to the previous description where 8 delocalized π-electrons were reported in metallabenzenes and metallabenzynes, we showed that only six delocalized π-electrons are present in those molecules.

DFT Study of Microsolvated [NO·(HO)] ( = 1-12) Clusters and Molecular Dynamics Simulation of Nitrate Solution.

Investigation of the process of the NO anion solvation is central to understanding the chemical and physical properties of its aqueous solutions. The importance of this topic can be seen in atmospheric chemistry, as well as in nuclear waste processing research. In this work, we used a particle swarm optimization technique driven by density functional theory to sample the potential energy surface of various microsolvated [NO·(HO)] ( = 1-12) clusters.

Photoelectron Spectroscopy of Size-Selected Bismuth-Boron Clusters: BiB ( = 6-8).

Because of its low toxicity, bismuth is considered to be a "green metal" and has received increasing attention in chemistry and materials science. To understand the chemical bonding of bismuth, here we report a joint experimental and theoretical study on a series of bismuth-doped boron clusters, BiB ( = 6-8). Well-resolved photoelectron spectra are obtained and are used to understand the structures and bonding of BiB in conjunction with theoretical calculations.

Ternary aromatic and anti-aromatic clusters derived from the hypho species [SnSb].

Heterometallic clusters have attracted broad interests in the synthetic chemistry due to their various coordination modes and potential applications in heterogeneous catalysis. Here we report the synthesis, experimental, and theoretical characterizations of four ternary clusters ([M(CO)SnSb] (M = Cr, Mo), and [(MSnSb)], (M = Cu, Ag)) in the process of capturing the hypho- [SnSb] in ethylenediamine (en) solution. We show that the coordination of the binary anion to transition-metal ions or fragments provides additional stabilization due to the formation of locally σ-aromatic units, producing a spherical aromatic shielding region in the cages.

The Rise of Neural Networks for Materials and Chemical Dynamics.

Machine learning (ML) is quickly becoming a premier tool for modeling chemical processes and materials. ML-based force fields, trained on large data sets of high-quality electron structure calculations, are particularly attractive due their unique combination of computational efficiency and physical accuracy. This Perspective summarizes some recent advances in the development of neural network-based interatomic potentials.

"Bottled" spiro-doubly aromatic trinuclear [PdRu] complexes.

Following an ongoing interest in the study of transition metal complexes with exotic bonding networks, we report herein the synthesis of a family of heterobimetallic triangular clusters involving Ru and Pd atoms. These are the first examples of trinuclear complexes combining these nuclei. Structural and bonding analyses revealed both analogies and unexpected differences for these [PdRu] complexes compared to their parent [Pd] peers.