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Context: The coherent electron/spin transport in azurin, a species of copper protein, was calculated based on the Landauer model. The research is motivated by the fast electron transport and spin selectivity/polarization in azurin, which have been reported in relation to the chiral-induced spin selectivity of the peptide structure. The calculated spin polarization of copper proteins was large. This phenomenon was strongly influenced by the spin density of the atoms in the ligand group, whereas the contribution of copper was negligible. The results suggest that spin polarization in copper proteins is enhanced by that of the ligand groups. The predicted spin polarization aligns primarily with the scanning tunneling microscope-based break-junction technique to study the electronic properties of single-molecule junctions. Methods: Computational techniques employed in this study are nonequilibrium Green's functions (NEGF) and density functional theory (DFT) based on the Landauer model, implemented using the QuantumATK software (Synopsys Inc.). The Perdew-Burke-Ernzerhof (PBE) exchange-correlation functional was adopted for spin-polarized generalized gradient approximation (SGGA). The valence atomic orbitals were constructed using the wavefunctions of the SIESTA package, which was based on the norm-conserving Troullier–Martins relativistic pseudopotentials for describing core electrons. The mesh used for real-space integration was 150 Ha. [ABSTRACT FROM AUTHOR]

Lanthanide-binding proteins have been examined for the specific lanthanide physical properties and the biological activities of peptide scaffolds. The chirality-induced spin selectivity (CISS) of helical peptide structures is a crucial aspect of spin polarization. Combining CISS-caused spin polarization with a paramagnetic lanthanide ion can yield protein-based memristance and protein sensing. In this study, coherent spin transport in a lanthanide-binding protein was examined based on first-principles calculations to discuss spin polarization in lanthanide-binding proteins. Among lanthanides, lanthanum-binding proteins, which exhibit no paramagnetic spin state, exhibit spin polarization in peptide structures. [ABSTRACT FROM AUTHOR]

The electronic transport properties of linear homocatenated indium chain were estimated through first-principle calculations. Long chains comprising four or five indium atoms exhibited a large transmission peak at the Fermi level, which enhanced their conductance. This peak was caused by enhanced σ-conjugation in the indium main chain. Due to σ-conjugation, the conductance did not monotonously attenuate under tunneling upon extension of molecular length. Therefore, homocatenation in indium chains is a promising candidate for molecular conduction. [ABSTRACT FROM AUTHOR]

Hydrosols containing silver nanoparticles were prepared from copolymers of ethylene glycol (EG) and vinyl pyrrolidone (VPy). The copolymers were synthesized using a macro-azo-radical initiator appended with EG units. The hydrosols were prepared by simply stirring the copolymers with AgNO in water at room temperature. The nanoparticles conferred thermal stability to the hydrosols, up to 80 °C. Spectroscopic, thermal, and gas chromatography analyses revealed that the silver nanoparticles were protected by EG and carbonyl groups with strong interaction between silver and the oxygen species of EG and VPy. [ABSTRACT FROM AUTHOR]

The band structures of metallocene-based polymers in which the nearest metalloecenes were directly linked by a C-C bond have been determined by employing the tight-binding crystal orbital (CO) method. In particular, we determined the band structures of metallocene-based alternate copolymers whose metal sequences in a unit cell were Fe-Co, Fe-Fe-Co-Co, Fe-Ni, Ru-Co and Os-Co. The band structures of alternate copolymers of Fe-Co and Fe-Ni possessed a partially occupied (PO) band whose crystal orbitals were extremely localized at the 3d orbitals of cobalt or nickel atom. Alternate copolymers of Ru-Co and Os-Co had the same tendency as that of band structure of Fe-Co. Therefore, it was clear that the band structures of the metallocene-based alternate copolymers were considered to be a superposition of the polymetallocenylenes. Furthermore, we examined the effect of inserting the bridging part of boron-, phosphorus-, and sulfur bridges between the nearest ferrocenes upon the band structures of ferrocene-based polymers. The electronic structure of the boron-bridged polymer was similar to that of the silicon-bridged polymer whose band structure was determined in our previous study. On the other hand, the phosphorus- and sulfur-bridged polymers yielded two degenerated HO bands whose COs were localized at P or S 2p orbitals. [ABSTRACT FROM AUTHOR]

This article presents a synthesis of a block copolymer of poly(methylphenylsilane) (PMPS) and 2-(methylthio)ethyl methacrylate (MTEM), P(MPS-co-MTEM), by photopolymerization using PMPS as a macro-photoinitiator and prepared a bilayer structure of P(MPS-co-MTEM) in which the copolymer is adsorbed to the gold layer. Polysilanes have been known as functional polymers with numerous electronic and optical properties such as photo-conductivity, electro- or photo-luminescence, due to the configuration of silicon-silicon main chain which is confirmed by conspicuous absorption band in the ultra-violet region. Organic-inorganic hybrid materials have also been known as promising materials for practical applications to electronic or optical devices. In order to improve some functionalities of polysilanes, polysilane-inorganic hybrid thin films were prepared in which polysilane segments are embedded in inorganic matrix such as silica, titania and zirconia. It was suggested that some chemical bonds or interactions between the organic and inorganic components are necessary to prepare homogenous organic-inorganic hybrids. Previously, chemical bonds between polysilane-acrylic or -methacrylic block copolymers and inorganic components via sol-gel reaction are used for preparation of homogeneous polysilane-silica or -titania hybrid thin films.