Ab initio calculations predict a metal-insulator transition at zero temperature to occur in La4Ni3O8 at moderate pressures as a result of a pressure-induced spin-state transition. The spin-state transition that is seen at 105 K at ambient pressure, from a low-temperature high-spin state to a high-temperature low-spin state, has been observed to be shifted to lower temperatures as pressure is ap...

Using density functional theory plus Hubbard U calculations, we show that the ground state of (Mg,Fe)(Si,Fe)O(3) perovskite, the major mineral phase in Earth's lower mantle, has high-spin ferric iron (S=5/2) at both dodecahedral (A) and octahedral (B) sites. With increasing pressure, the B-site iron undergoes a spin-state crossover to the low-spin state (S=1/2) between 40 and 70 GPa, while the ...

9 Using density functional theory plus Hubbard U calculations, we show that the ground state of 10 (Mg,Fe)(Si,Fe)O3 perovskite, the major mineral phase in the Earth’s lower mantle, has high-spin 11 ferric iron (S = 5/2) at both dodecahedral (A) and octahedral (B) sites. With increasing pressure, 12 the B-site iron undergoes a spin-state crossover to the low-spin state (S = 1/2) between 40 and 1...

We study the magnetic susceptibility of mixed-valent La2−xSrxCoO4 single crystals in the doping range of 0.5 x 0.8 for temperatures up to 1000 K. The magnetism below room temperature is described by paramagnetic Co2+ in the high-spin state and by Co3+ in the nonmagnetic low-spin state. At high temperatures, an increase in susceptibility is seen, which we attribute to a temperature-induced spin-...

We propose a physically reversible quantum measurement of an arbitrary spin-s system using a spin-j probe with a simple interaction. By the physical reversibility, the measurement has a reversing measurement, which can restore the premeasurement state from the postmeasurement state with a nonzero probability of success. In the case of a spin-1/2 system (s = 1/2), we explicitly construct such a ...

Structural changes of the iron(II)-tris-bipyridine ([Fe(II)(bpy)(3)](2+)) complex induced by ultrashort pulse excitation and population of its short-lived (< or =0.6 ns) quintet high spin state have been detected by picosecond x-ray absorption spectroscopy. The structural relaxation from the high spin to the low spin state was followed over the entire lifetime of the excited state. A combined a...

The covariant spectator (or Gross) equations for the bound state of three identical spin 1/2 particles, in which two of the three interacting particles are always on shell, are developed and reduced to a form suitable for numerical solution. The equations are first written in operator form and compared to the Bethe-Salpeter equation, then expanded into plane wave momentum states, and finally ex...

The heme-containing cytochrome P450s exhibit isoform-dependent ferric spin equilibria in the resting state and differential substrate-dependent spin equilibria. The basis for these differences is not well understood. Here, magnetic circular dichroism (MCD) reveals significant differences in the resting low spin ligand field of CYPs 3A4, 2E1, 2C9, 125A1, and 51B1, which indicates differences in ...

A nanoscale molecular switch can be used to store information in a single molecule. Although the switching process can be detected electrically in the form of a change in the molecule's conductance, adding spin functionality to molecular switches is a key concept for realizing molecular spintronic devices. Here we show that iron-based spin-crossover molecules can be individually and reproducibl...