Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Intermediate phase, network demixing, boson and floppy modes, and
  compositional trends in glass transition temperatures of binary AsxS1-x
  system   The structure of binary As_xS_{1-x} glasses is elucidated using
modulated-DSC, Raman scattering, IR reflectance and molar volume experiments
over a wide range (8%<x<41%) of compositions. We observe a reversibility window
in the calorimetric experiments, which permits fixing the three elastic phases;
flexible at x<22.5%, intermediate phase (IP) in the 22.5%<x<29.5% range, and
stressed-rigid at x>29.5%. Raman scattering supported by first principles
cluster calculations reveal existence of both pyramidal (PYR, As(S1/2)3) and
quasi-tetrahedral(QT, S=As(S1/2)3) local structures. The QT unit concentrations
show a global maximum in the IP, while the concentration of PYR units becomes
comparable to those of QT units in the phase, suggesting that both these local
structures contribute to the width of the IP. The IP centroid in the sulfides
is significantly shifted to lower As content x than in corresponding selenides,
a feature identified with excess chalcogen partially segregating from the
backbone in the sulfides, but forming part of the backbone in selenides. These
ideas are corroborated by the proportionately larger free volumes of sulfides
than selenides, and the absence of chemical bond strength scaling of Tgs
between As-sulfides and As-selenides. Low-frequency Raman modes increase in
scattering strength linearly as As content x of glasses decreases from x = 20%
to 8%, with a slope that is close to the floppy mode fraction in flexible
glasses predicted by rigidity theory. These results show that floppy modes
contribute to the excess vibrations observed at low frequency. In the
intermediate and stressed rigid elastic phases low-frequency Raman modes
persist and are identified as boson modes. Some consequences of the present
findings on the optoelectronic properties of these glasses is commented upon.

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The categories of this paper are: hep-ph
7
The categories of this paper are: hep-th
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
34
The categories of this paper are: chem-ph
8
The categories of this paper are: hep-ex
11
The categories of this paper are: hep-lat
10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con
33
The categories of this paper are: plasm-ph
1
The categories of this paper are: cs
15
The categories of this paper are: nucl-ex
25
The categories of this paper are: patt-sol
17
The categories of this paper are: q-fin
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys