Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The effect of pressure and spin on the isotopic composition of ferrous
  iron dissolved in periclase and silicate perovskite   We perform density functional calculations of the equilibrium 57Fe/54Fe
ratios for ferrous iron dissolved in periclase and MgSiO3 perovskite at the
pressures and temperatures of the Earth's mantle. Pressure increases the
partitioning of 57Fe into both phases by a factor of three from the Earth's
surface to the core-mantle boundary. In ferropericlase, a large contribution to
this increase comes from the electronic transition from high-spin to low-spin
iron. Our calculations demonstrate that pressure-induced fractionation can play
a major role in determining planetary iron-isotope composition.

7
The categories of this paper are: hep-th
15
The categories of this paper are: nucl-ex
8
The categories of this paper are: hep-ex
16
The categories of this paper are: stat
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th
22
The categories of this paper are: chao-dyn
17
The categories of this paper are: q-fin
28
The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
12
The categories of this paper are: nucl-th
26
The categories of this paper are: bayes-an
32
The categories of this paper are: atom-ph