The title compounds, a hydrogen-bonded linear chain, [Mn(C18H18N2O4)(H2O)2]ClO4, (I), a hydrogen-bonded pseudo-dimer, [Mn(C16H10Cl4N2O2)(CH4O)(H2O)]ClO4, (II), and a dimer, [Mn2(C18H18N2O4)2(CH4O)2](ClO4)2, (III), respectively, have been structurally characterized. The three complexes are completely different in their structural features, despite identical counter-anions and only slight modification of the substituents in the ligands. Complex (I) affords an elongated octahedral coordination environment, with axial Mn-O(water) distances of 2.259 (3) and 2.313 (3) A, which forms hydrogen-bonded linear chains along the crystallographic c axis. Hydrogen-bonded pseudo-dimeric compound (II) also affords an elongated octahedral coordination environment, with axial Mn-O(CH3OH) = 2.222 (3) A and Mn-O(water) = 2.266 (3) A. Dimeric complex (III) is centrosymmetric and consists of distorted octahedral Mn atoms, with axial Mn-O(CH3OH) = 2.242 (2) A and Mn-O(phenolate) = 2.348 (1) A, connected via bridging O atoms from one of the ligands. The magnetic properties of the three complexes are described.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1107/S0108270105013545 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Extending Badger's rule. I. The relationship between energy and structure in hydrogen bonds.
J Chem Phys
January 2025
Department of Chemistry, University of Washington, Seattle, Washington 98185, USA.
We derive a new expression for the strength of a hydrogen bond (VHB) in terms of the elongation of the covalent bond of the donor fragment participating in the hydrogen bond (ΔrHB) and the intermolecular coordinates R (separation between the heavy atoms) and θ (deviation of the hydrogen bond from linearity). The expression includes components describing the covalent D-H bond of the hydrogen bond donor via a Morse potential, the Pauli repulsion, and electrostatic interactions between the constituent fragments using a linear expansion of their dipole moment and a quadratic expansion of their polarizability tensor. We fitted the parameters of the model using ab initio electronic structure results for six hydrogen bonded dimers, namely, NH3-NH3, H2O-H2O, HF-HF, H2O-NH3, HF-H2O, and HF-NH3, and validated its performance for extended parts of their potential energy surfaces, resulting in a mean absolute error ranging from 0.
View Article and Find Full Text PDFQuantitative Estimation of Effective Brønsted Acid Sites of Silica-Supported HSiWO Heteropoly Acid for Adsorption of Various Molecules.
Langmuir
January 2025
Institute for Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan.
The amount of incorporation of linear alcohols and ethers in HSiWO·6HO (HSiW·6HO, 50 wt %) supported on silica (SiO) was estimated by a conventional volumetric method and infrared (IR) spectroscopy, and the state of involved molecules was elucidated. First, the attribution of the key IR band at 2200 cm, which was observed for the water of crystallization of HSiW·6HO, to HO species (protons) was verified by coincident observation of thermogravimetric-differential thermal analysis, X-ray diffraction (XRD), and IR spectroscopy during thermal treatment in addition to the isotope exchange with DO. The 2200 cm band was gradually decreased in intensity by increasing the amount of adsorption of pyridine and was totally consumed at saturation, while the volumetric method provided the accurate number of included pyridine molecules.
View Article and Find Full Text PDFSelective Self-Assembly of Supramolecular Helices and Macrocycles Directed by Halogen Bonding.
Chemistry
December 2024
Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China.
In this study, several hydrogen-bonded arylamide foldamers (compounds 1-5) with the same degree of polymerization were designed and synthesized. The polyfluoroiodobenzene or iodoethynyl polyfluoroiodobenzene segment was modified as a halogen donor at the end of the monomer, and pyridine or pyridine oxynitride served as the corresponding halogen acceptor segment. The crystal structure of compound 1 indicates that the supramolecular double helices were constructed by stacking a P helix and an M helix in an antiparallel manner in the direction of intermolecular I⋅⋅⋅O-N halogen bonding.
View Article and Find Full Text PDFPhysically crosslinked polyacrylates by quadruple hydrogen bonding side chains.
J Mater Chem B
December 2024
Supramolecular Chemistry Group, Centre of Macromolecular Chemistry (CMaC), Department of Organic and Macromolecular Chemistry, Ghent University, B-9000 Ghent, Belgium.
Dynamic polymer materials can be obtained by introducing supramolecular interactions between the polymer chains. Here we report on the preparation and mechanical properties of poly(methyl acrylate) (PMA) and poly(-butyl acrylate) (PBA) funcionalized with ureidopyrimidinone (UPy) in the side chains. In contrast to the traditional UPy with a methyl group, the selected UPy motif contained a branched alkyl side chain, which enhances solubility, compatibility with the polymer matrix and potentially prevents stacking of UPy dimers.
View Article and Find Full Text PDFHOF-derived Step-Scheme FJU-200@CdSe heterojunction: A photoelectrochemical sensing platform for sensitive detection of EGFR.
Biosens Bioelectron
January 2025
Department of Pharmacy, The First Hospital of China Medical University, Shenyang, Liaoning, 110001, PR China; School of Pharmacy, China Medical University, Shenyang, Liaoning, 110122, PR China. Electronic address:
Here, a photoelectrochemical (PEC) immunosensor based on the FJU-200@CdSe heterostructure was developed for epidermal growth factor receptor (EGFR) detection. This is the first application of FJU-200 in PEC. After modification using CdSe quantum dots (QDs), FJU-200 and CdSe QDs formed an S-scheme heterostructure due to the interleaved energy band structure and the difference in Fermi energy (Ef) levels, which generated an efficient and stable PEC signal.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!