Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: FourPhonon: An extension module to ShengBTE for computing four-phonon
  scattering rates and thermal conductivity   FourPhonon is a computational package that can calculate four-phonon
scattering rates in crystals. It is built within ShengBTE framework, which is a
well-recognized lattice thermal conductivity solver based on Boltzmann
transport equation. An adaptive energy broadening scheme is implemented for the
calculation of four-phonon scattering rates. In analogy with $thirdorder.py$ in
ShengBTE, we also provide a separate python script, $Fourthorder.py$, to
calculate fourth-order interatomic force-constants. The extension module
preserves all the nice features of the well-recognized lattice thermal
conductivity solver ShengBTE, including good parallelism and straightforward
workflow. In this paper, we discuss the general theory, program design, and
example calculations on Si, BAs and $\mathrm{LiCoO_2}$.

3
The categories of this paper are: physics
13
The categories of this paper are: quant-ph
28
The categories of this paper are: alg-geom
23
The categories of this paper are: solv-int
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
0
The categories of this paper are: hep-ph
33
The categories of this paper are: plasm-ph
24
The categories of this paper are: dg-ga
12
The categories of this paper are: nucl-th
18
The categories of this paper are: econ
35
The categories of this paper are: mtrl-th
27
The categories of this paper are: comp-gas
6
The categories of this paper are: astro-ph
11
The categories of this paper are: hep-lat
10
The categories of this paper are: q-bio