相关论文: Magnetic mechanism for the biological functioning …
Hemoglobin (Hb) is a multifaceted protein, classified as a metalloprotein, chromoprotein, and globulin. It incorporates iron, which plays a crucial role in transporting oxygen within red blood cells. Hb functions by carrying oxygen from the…
An ab initio study of the electronic and spin configuration for the iron ion in the active center of the human hemoglobin molecule is presented. It is well known that the iron ion, being surrounded by the porphyrin ring and the ligands,…
We developed a new mechanical model for determining the compression and shear mechanical behavior of four different hemoglobin structures. Previous studies on hemoglobin structures have focused primarily on overall mechanical behavior;…
The effects of magnetism on high pressure properties of transition metals and transition metal compounds can be quite important. In the case of Fe, magnetism is responsible for stability of the body-centered cubic (bcc) phase at ambient…
This work reports the measurement of magnetic dichroism in angular-resolved photoemission from in-plane magnetized buried thin films. The high bulk sensitivity of hard X-ray photoelectron spectroscopy (HAXPES) in combination with circularly…
This is an analysis of how magnetic fields affect biological molecules and cells. It was prompted by a series of prominent reports regarding magnetism in biological systems. The first claims to have identified a protein complex that acts…
We have used the Stern-Gerlach deflection technique to study magnetism in chromium clusters of 20-133 atoms. Between 60 K and 100 K, we observe that these clusters have large magnetic moments and respond superparamagnetically to applied…
Magnetic properties of metals are investigated through electronic structure calculations based on the recently-proposed magnetic-field-containing relativistic tight-binding approximation (MFRTB) method [Phys. Rev. B \textbf{91}, 075122…
A theory is developed of the time-dependent magnetization of the metacrystal composed of magnetoferritin macromolecules. Such superstructures, comprising up to several millions of superparamagnetic nanoparticles encapsulated in protein…
The first X-ray magnetic circular dichroism (XMCD) spectra on the title compounds are presented. In Mn12 the Mn(III) and Mn(IV) contributions are clearly apparent and evidence the opposite spin arrangement of the two ions. For Fe8 the…
The orbital contribution to the magnetic properties of Fe in systems of decreasing dimensionality (bulk, surfaces, wire and free clusters) is investigated using a tight-binding hamiltonian in an $s, p,$ and $d$ atomic orbital basis set…
Low temperature M\"ossbauer spectroscopic and magnetization measurements were performed on a crystalline sample of Fe-gluconate. Fe atoms were revealed to exist in two phases i.e. a major (90-94 pct.) and a minor (6-10 pct.). Based on…
We use density functional theory based first-principles methods to study the magnetism in a 2D hexagonal BN sheet induced by the different concentrations of oxygen and silicon atoms substituting for nitrogen (O$_\mathrm{N}$) and boron…
The oxidation and spin state of a metal-organic molecule determine its chemical reactivity and magnetic properties. Here, we demonstrate the reversible control of the oxidation and spin state in a single Fe-porphyrin molecule in the force…
We present a joint experimental and theoretical characterization of the magnetic properties of coordination clusters with an antiferromagnetic core of four magnetic ions. Two different compounds are analyzed, with Co and Mn ions in the…
The synthesis of molecular magnets has undergone rapid progress in recent years. Each of the identical molecular units can contain as few as two and up to several dozens of paramagnetic ions (spins). Although these materials appear as…
Abnormal hemoglobins can have major consequences for tissue delivery of oxygen. Correct diagnosis of hemoglobinopathies with altered oxygen affinity requires a determination of hemoglobin oxygen dissociation curve (ODC), which relates the…
In order to investigate the mechanism of ferromagnetic ordering in the new n-type magnetic semiconductor (In,Fe)As co-doped with Be, we have performed X-ray absorption spectroscopy and X-ray magnetic circular dichroism (XMCD) studies of…
Band calculations for supercells of La$_{(2-x)}$Ba$_x$CuO$_4$ show that the rigid band model for doping is less adequate than what is commonly assumed. In particular, weak ferromagnetism (FM) can appear locally around clusters of high Ba…
From magnetic deflection experiments on isolated Co doped Nb clusters we made the interesting observation of some clusters being magnetic, while others appear to be non-magnetic. There are in principle two explanations for this behavior.…