Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Intermolecular mechanism for multiple maxima in molecular dynamic
  susceptibility   A simple two-level system is introduced to demonstrate the existence of the
intermolecular mechanism of the appearance/disappearance of multiple maxima in
molecular dynamic susceptibility at low temperature. With minimum two
relaxation processes, quantum tunneling induced by the nuclear spin bath and
the direct process due to the spin-phonon interaction, we prove that the
existence of a sufficiently wide dipolar field distribution in the experimental
sample is the main cause of this phenomenon in zero or weak applied dc field.
The correlations between the phenomenon and the applied dc field, temperature,
or magnetic dilution of the sample are also investigated. Application to
several experimental systems has shown a good agreement between the proposed
theory and experiments. Cases with more complex multiplet spectrum, more
relaxation processes,and possibility of more maxima in the molecular dynamic
susceptibility are discussed.

14
The categories of this paper are: math-ph
23
The categories of this paper are: solv-int
37
The categories of this paper are: supr-con
36
The categories of this paper are: cmp-lg
19
The categories of this paper are: eess
18
The categories of this paper are: econ
16
The categories of this paper are: stat
27
The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
17
The categories of this paper are: q-fin
2
The categories of this paper are: math
24
The categories of this paper are: dg-ga
15
The categories of this paper are: nucl-ex
7
The categories of this paper are: hep-th
11
The categories of this paper are: hep-lat
26
The categories of this paper are: bayes-an