Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spin-Phonon Relaxation in Molecular Qubits from First Principles Spin
  Dynamics   The coupling between electronic spins and lattice vibrations is fundamental
for driving relaxation in magnetic materials. The debate over the nature of
spin-phonon coupling dates back to the 40's, but the role of spin-spin,
spin-orbit and hyperfine interactions, has never been fully established. Here
we present a comprehensive study of the spin dynamics of a crystal of
Vanadyl-based molecular qubits by means of first-order perturbation theory and
first-principles calculations. We quantitatively determine the role of the
Zeeman, hyperfine and electronic spin dipolar interactions in the direct
mechanism of spin relaxation. We show that, in a high magnetic field regime,
the modulation of the Zeeman Hamiltonian by the intra-molecular components of
the acoustic phonons dominates the relaxation mechanism. In low fields,
hyperfine coupling takes over, with the role of spin-spin dipolar interaction
remaining the less important for the spin relaxation.

10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
26
The categories of this paper are: bayes-an
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The categories of this paper are: q-alg
1
The categories of this paper are: cs
5
The categories of this paper are: gr-qc
34
The categories of this paper are: chem-ph
31
The categories of this paper are: ao-sci
25
The categories of this paper are: patt-sol
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The categories of this paper are: acc-phys
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The categories of this paper are: solv-int
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The categories of this paper are: hep-lat
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The categories of this paper are: astro-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: eess
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The categories of this paper are: cmp-lg