Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Fragile 3D Order in V$_{1-x}$Mo$_x$O$_2$   The metal-to-insulator transition (MIT) in rutile VO$_2$ has proven uniquely
difficult to characterise because of the complex interplay between electron
correlations and atomic structure. A number of approaches have been explored
since its discovery, relying on some combination of Mott localization, Peierls
distortions, superexchange, and orbital ordering to explain the structural
instability at the MIT. Here we report the discovery of the sudden collapse of
three-dimensional order in the low-temperature phase of V$_{1-x}$Mo$_x$O$_2$ at
$x=0.17$ and the emergence of a novel frustrated two-dimensional order at
$x=0.19$, with only a slight change in electronic properties. Single crystal
diffuse x-ray scattering reveals that this transition from the 3D M1 phase to a
2D variant of the M2 phase results in long-range structural correlations along
symmetry-equivalent (11L) planes of the tetragonal rutile structure, yet
extremely short-range correlations transverse to these planes. These findings
emphasise the fragility of structural order in VO$_2$, the role of geometric
frustration, and the need for improved electronic structure models.

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The categories of this paper are: adap-org
16
The categories of this paper are: stat
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
28
The categories of this paper are: alg-geom
24
The categories of this paper are: dg-ga
15
The categories of this paper are: nucl-ex
18
The categories of this paper are: econ
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
17
The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
14
The categories of this paper are: math-ph