Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Superconductivity of novel tin hydrides (Sn$_n$H$_m$) under pressure   With the motivation of discovering high-temperature superconductors,
evolutionary algorithm is employed to search for all stable compounds in the
Sn-H system. In addition to the traditional SnH$_4$, new hydrides SnH$_8$,
SnH$_{12}$ and SnH$_{14}$ are found to be thermodynamically stable at high
pressure. Dynamical stability and superconductivity of tin-hydrides are
systematically investigated. I$\bar{4}$m2-SnH$_8$, C2/m-SnH$_{12}$ and
C2/m-SnH$_{14}$ exhibit higher superconducting transition temperatures of 81,
93 and 97 K compared to the traditional compound SnH$_4$ with T$_c$ of 52 K at
200 GPa. An interesting bent H$_3^-$ in I$\bar{4}$m2-SnH$_8$ and novel liner
H$_4^-$ in C2/m-SnH$_{12}$ are observed. All the new tin-hydrides remain
metallic over their predicted range of stability. The intermediate-frequency
wagging and bending vibrations have more contribution to electron-phonon
coupling parameter than high-frequency stretching vibrations of H$_2$ and
H$_3$.

34
The categories of this paper are: chem-ph
15
The categories of this paper are: nucl-ex
36
The categories of this paper are: cmp-lg
20
The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th
27
The categories of this paper are: comp-gas
1
The categories of this paper are: cs
25
The categories of this paper are: patt-sol
9
The categories of this paper are: nlin
37
The categories of this paper are: supr-con
14
The categories of this paper are: math-ph
13
The categories of this paper are: quant-ph
11
The categories of this paper are: hep-lat
12
The categories of this paper are: nucl-th
21
The categories of this paper are: adap-org
6
The categories of this paper are: astro-ph