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Herein we have evidenced the formation of favorable π‐hole Br⋅⋅⋅metal noncovalent interactions (NCIs) involving elements from groups 9, 11 and 12. More in detail, M (M=Co2+, Ni2+, Cu2+ and Zn2+) containing porphyrins have been synthesized and their supramolecular assemblies structurally characterized by means of single crystal X‐ray diffraction and Hirshfeld surface analyses, revealing the formation of directional Br⋅⋅⋅M contacts in addition to ancillary hydrogen bond and lone pair‐π bonds. Computations at the PBE0‐D3/def2‐TZVP level of theory revealed the π‐hole nature of the Br⋅⋅⋅M interaction. In addition, the physical nature of these NCIs was studied using Quantum Chemistry methodologies, providing evidence of π‐hole Spodium and Regium bonds in Zn2+ and Cu2+ porphyrins, in addition to unveiling the presence of a π‐hole for group 9 (Co2+). On the other hand, group 10 (Ni2+) acted as both electron donor and acceptor moiety without showing an electropositive π‐hole. Owing to the underexplored potential of π‐hole interactions in transition metal chemistry, we believe the results reported herein will be useful in supramolecular chemistry, organometallics, and solid‐state chemistry by i) putting under the spotlight the π‐hole chemistry involving first row transition metals and ii) unlocking a new tool to direct the self‐assembly of metalloporphyrins. [ABSTRACT FROM AUTHOR]

Herein we have computationally evaluated the relationship between Ag and Au nanoparticle (Ag/AuNP) size and π-surface extension in the formation of noncovalent complexes at the PBE0-D3/def2-TZVP level of theory. The NP-π interaction is known in supramolecular chemistry as a Regium-π bond (Rg-π), and differentiates from classical coordination bonds in strength and type of metal orbitals involved. In this study, the Rg-π complexes involved small Ag/AuNPs composed by 1 to 5 atoms and benzene, naphthalene and anthracene as π-systems, being characterized using several molecular modeling tools, including molecular electrostatic potential (MEP) calculations, energy decomposition analysis (EDA), quantum theory of atoms in molecules (QTAIM), non covalent interaction plot (NCIplot) and natural bonding orbital (NBO) methodologies. We believe the results reported herein will be useful for those scientists working in catalysis, molecular recognition and materials science fields, where structural-energetic relationships of weak interactions are crucial to achieve product selectivity, a particular molecular recognition mode or a specific molecular assembly. [ABSTRACT FROM AUTHOR]

A Protein Data Bank (PDB) survey has revealed noncovalent contacts involving Mn centres and protein residues. Their geometrical features are in line with the interaction between low electron density sites located along the Mn–O/N coordination bonds (σ-holes) and the lone pairs belonging to TYR, SER or HIS residues, known as a matere bond (MaB). Calculations at the PBE0-D3/def2-TZVP level of theory were used to investigate the strength and shed light on the physical nature of the interaction. We expect the results presented herein will be useful for those scientists working in the fields of bioinorganic chemistry, particulary in protein–metal docking, by providing new insights into transition metal⋯Lewis base interactions as well as a retrospective point of view to further understand the structural and functional implications of this key transition metal ion. [ABSTRACT FROM AUTHOR]

Metallophilic interactions, specifically argentophilic (Ag⋯Ag) and aurophilic (Au⋯Au) interactions, play a crucial role in stabilizing various molecular and solid-state structures. In this manuscript, we present a convenient method to estimate the strength of argentophilic and aurophilic interactions based on quantum theory of atoms in molecules (QTAIM) parameters evaluated at the bond critical points connecting the metal centres. We employ density functional theory (DFT) calculations and the QTAIM parameters to develop this energy predictor. To validate the reliability and applicability of our method, we test it using a selection of X-ray crystal structures extracted from the cambridge structural database (CSD), where argentophilic and aurophilic interactions are known to be significant in their solid-state arrangements. This method offers a distinct advantage in systems where multiple interactions, beyond metallophilic interactions, contribute to the overall stability of the structure. By employing our approach, researchers can distinctly quantify the strength of argentophilic and aurophilic interactions, facilitating a deeper understanding of their impact on molecular and solid-state properties. This method fills a critical gap in the existing literature, offering a valuable tool to researchers seeking to unravel the intricate interactions in metal-containing compounds. [ABSTRACT FROM AUTHOR]

The article titled "Inside Back Cover: From Coordination to π-Hole Chemistry of Transition Metals: Metalloporphyrins as a Case of Study" explores the use of metalated porphyrins in outer space to form noncovalent Br⋅⋅⋅M interactions. The cover image depicts a dragon using its nest as a template to assemble the metal ion into the porphyrin's core, interacting with it using orbs located on its head and tail. The authors, Antonio Bauzá, Ranjan Patra, and others, provide a computational analysis of these interactions in the solid state. [Extracted from the article]

The article titled "From Coordination to π-Hole Chemistry of Transition Metals: Metalloporphyrins as a Case of Study" explores the π-hole nature of metalated porphyrins in outer space. The authors discuss the formation of noncovalent Br⋅⋅⋅M interactions (M = Co2+, Ni2+, Cu2+, and Zn2+) and present a computational analysis of these interactions in the solid state. The cover image depicts a dragon using its nest as a template to assemble the metal ion into the porphyrin's core, interacting with it using orbs located on its head and tail. The authors of the article are Antonio Bauzá, Ranjan Patra, and others. [Extracted from the article]

The Protein Data Bank (PDB) was scrutinized for the presence of noncovalent O···Al Triel Bonding (TrB) interactions, involving protein residues (e.g. GLU and GLN), adenosine/guanine diphosphate moieties (ADP and GDP), water molecules and two aluminum fluorides (AlF3 and AlF4-). The results were statistically analyzed, revealing a vast number of O···Al contacts in the active sites of phosphoryl transfer enzymes, with a marked directionality towards the Al σ-/π-hole. The physical nature of the TrBs studied herein was analyzed using Molecular Electrostatic Potential (MEP) maps, the Quantum Theory of Atoms in Molecules (QTAIM), the Non Covalent Interaction plot (NCIplot) visual index and Natural Bonding Orbital (NBO) studies. As far as our knowledge extends, it is the first time that O···Al TrBs are analyzed within a biological context, participating in protein trapping mechanisms related to phosphoryl transfer enzymes. Moreover, since they are involved in the stabilization of aluminum fluorides inside the protein's active site, we believe the results reported herein will be valuable for those scientists working in supramolecular chemistry, catalysis and rational drug design., (© 2024 Wiley‐VCH GmbH.)

In this manuscript we evaluate the X-ray structure of five new pertechnetate derivatives of general formula [M(H 2 O) 4 (TcO 4 ) 2 ], M=Mg, Co, Ni, Cu, Zn (compounds 1-5) and one perrhenate compound Zn(H 2 O) 4 (ReO 4 ) 2 (6). In these complexes the metal center exhibits an octahedral coordination with the pertechnetate units as axial ligands. All compounds exhibit the formation of directional Tc⋅⋅⋅O Matere bonds (MaBs) that propagate the [M(H 2 O) 4 (TcO 4 ) 2 ], into 1D supramolecular polymers in the solid state. Such 1D polymers are linked, generating 2D layers, by combining additional MaBs and hydrogen bonds (HBs). Such concurrent motifs have been analyzed theoretically, suggesting the noncovalent σ-hole nature of the MaBs. The interaction energies range from weak (~ -2 kcal/mol) for the MaBs to strong (~ -30 kcal/mol) for the MaB+HB assemblies, where HB dominates. In case of M=Zn, the corresponding perrhenate Zn(H 2 O) 4 (ReO 4 ) 2 complex, has been also synthesized for comparison purposes, resulting in the formation of an isostructural X-ray structure, corroborating the structure-directing role of Matere bonds., (© 2024 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)