Perturbed angular correlation of gamma-rays (PAC) spectroscopy of cadmium substituted plastocyanin shows one dominant metal site configuration at pH 7.5. Lowering the pH to 4.8 a fraction of the molecules undergoes structural change and loses the bound cadmium ion. At pH 4.4 all plastocyanin is in the apo-form. Increasing the pH back to neutral pH values two distinct metal site coordination geometries were observed. One of the two signals is the same as that found initially at pH 7.5; the other form is stable for hours at 1 degrees C, indicating the existence of a long lived intermediate metal site structure. The cadmium ion is surrounded by the same ligands (His37, Cys84, His87 and Met92) in both forms, however the metal center in the long lived intermediate metal site structure can be best described by a larger His-metal-His angle.
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http://dx.doi.org/10.1016/j.febslet.2006.09.076 | DOI Listing |
ACS Nano
January 2025
Department of Chemistry, School of Science and Key Laboratory for Quantum Materials of Zhejiang Province, Research Center for Industries of the Future, Westlake University, Hangzhou 310030, China.
In our previous studies of metal nanoparticle growth, we have come to realize that the dynamic interplay between ligand passivation and metal deposition, as opposed to static facet control, is responsible for focused growth at a few active sites. In this work, we show that the same underlying principle could be applied to a very different system and explain the abnormal growth modes of liquid nanoparticles. In such a liquid active surface growth (LASG), the interplay between droplet expansion and simultaneous silica shell encapsulation gives rise to an active site of growth, which eventually becomes the long necks of nanobottles.
View Article and Find Full Text PDFAnal Chem
January 2025
State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Hydroquinone (HQ) and copper ions (Cu) are categorized as environmental pollutants that are severely limited in water. Designing a selective assay for discriminating HQ from its two isomers and the convenient determination of Cu is of great importance. Herein, a Tb-based metal-organic framework (Tb-MOF) and HQ are assembled innovatively into a ratiometric fluorescence nanoprobe to selectively distinguish HQ and subsequent quantitative visual detection of Cu.
View Article and Find Full Text PDFACS Nano
January 2025
WA School of Mines: Minerals, Energy and Chemical Engineering, Curtin University, Perth, WA 6102, Australia.
Quadruple perovskite oxides have received extensive attention in electronics and catalysis, owing to their cation-ordering structure and intriguing physical properties. However, their repertoires still remain limited. In particular, piezoelectricity from quadruple perovskites has been rarely reported due to the frustrated symmetry-breaking transition in A-site-ordered perovskite structures, disabling their piezoelectric applications.
View Article and Find Full Text PDFInorg Chem
January 2025
University of Göttingen, Institute of Inorganic Chemistry, Tammannstrasse 4, D-37077 Göttingen, Germany.
Alkyl nickel intermediates relevant to catalytic processes often feature agostic stabilization, but relatively little is known about the situation in oligonickel systems. The dinickel(I) complex K[LNi], which is based on a compartmental pyrazolato-bridged ligand L with two β-diketiminato chelate arms, or its masked version, the dihydride complex [KL(Ni-H)] that readily releases H, oxidatively add methyl tosylate to give diamagnetic [LNi(CH)] () with (Ni···Ni) ≈ 3.7 Å.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
New Chemistry Unit, International Centre for Materials Science and School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bangalore, Jakkur P.O. 560064, India.
Seeking new and efficient thermoelectric materials requires a detailed comprehension of chemical bonding and structure in solids at microscopic levels, which dictates their intriguing physical and chemical properties. Herein, we investigate the influence of local structural distortion on the thermoelectric properties of TlCuS, a layered metal sulfide featuring edge-shared Cu-S tetrahedra within CuS layers. While powder X-ray diffraction suggests average crystallographic symmetry with no distortion in CuS tetrahedra, the synchrotron X-ray pair distribution function experiment exposes concealed local symmetry breaking, with dynamic off-centering distortions of the CuS tetrahedra.
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