Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Effect of molecular constitution and conformation on positron binding
  and annihilation in alkanes   The model-potential approach previously developed by the authors to study
positron interactions with molecules is used to calculate the positron binding
energy for $n$-alkanes (C$_n$H$_{2n+2}$) and the corresponding cycloalkanes
(C$_n$H$_{2n}$). For $n$-alkanes, the dependence of the binding energy on the
conformation of the molecule is investigated, with more compact structures
showing greater binding energies. As a result, thermally averaged binding
energies for larger alkanes ($n\gtrsim 9$) show a strong temperature dependence
in the range of 100-600 K. This suggests that positron resonant annihilation
can be used as a probe of rotational (trans-gauche) isomerization of
$n$-alkanes. In particular, the presence of different conformers leads to
shifts and broadening of vibrational Feshbach resonances in the annihilation
rate, as observed with a trap-based low-energy positron beam.

22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol
2
The categories of this paper are: math
23
The categories of this paper are: solv-int
10
The categories of this paper are: q-bio
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
35
The categories of this paper are: mtrl-th
9
The categories of this paper are: nlin
29
The categories of this paper are: funct-an
5
The categories of this paper are: gr-qc
1
The categories of this paper are: cs
11
The categories of this paper are: hep-lat
17
The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
32
The categories of this paper are: atom-ph