Magnetic ground state of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>La</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:mi>Li</mml:mi><mml:mi>Mo</mml:mi><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mn>6</mml:mn></mml:msub></mml:mrow></mml:math>: A comparison with other <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msup><mml:mrow><mml:mi>Mo</mml:mi></mml:mrow><mml:mrow><mml:mn>5</mml:mn><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:math> (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>S</mml:mi><mml:mo>=</mml:mo><mml:mn>1</mml:mn><mml:mo>/</mml:mo><mml:mn>2</mml:mn></mml:mrow></mml:math>) double perovskites
Bibliographic record
Abstract
${\mathrm{La}}_{2}\mathrm{Li}\mathrm{Mo}{\mathrm{O}}_{6}$ is a double perovskite (DP) with $P{2}_{1}/n$ symmetry based on the ${\mathrm{Mo}}^{5+}$ ion, $4{d}^{1}$, ${{t}_{2\mathrm{g}}}^{1}$, $S=1/2$. It is isostructural with ${\mathrm{Sr}}_{2}\mathrm{Y}\mathrm{Mo}{\mathrm{O}}_{6}$, the magnetic ground state of which is apparently a very unusual collective spin singlet or valence-bond glass state as is the case for cubic ($Fm\text{\ensuremath{-}}3m$) ${\mathrm{Ba}}_{2}\mathrm{Y}\mathrm{Mo}{\mathrm{O}}_{6}$. Initial studies of ${\mathrm{La}}_{2}\mathrm{Li}\mathrm{Mo}{\mathrm{O}}_{6}$ suggested a different ground state from the other DPs but no clear conclusions could be drawn. A more detailed study is presented here including magnetic susceptibility, heat capacity, and elastic neutron-scattering results. This DP is now well characterized as an antiferromagnet, ${T}_{\mathrm{N}}=18\phantom{\rule{0.16em}{0ex}}\mathrm{K}$, via observation of magnetic Bragg peaks in neutron scattering and an anomaly in the magnetic heat capacity. The ordering wave vector is $\mathbit{k}=(1/2\phantom{\rule{4pt}{0ex}}1/2\phantom{\rule{0.16em}{0ex}}0)$, consistent with a type I face-centered-cubic magnetic structure, and the ordered moment on ${\mathrm{Mo}}^{5+}$ is $0.32(11)\phantom{\rule{0.16em}{0ex}}{\ensuremath{\mu}}_{\mathrm{B}}$, much reduced from the spin-only value of $1\phantom{\rule{0.16em}{0ex}}{\ensuremath{\mu}}_{\mathrm{B}}$. The index, $f=|{\ensuremath{\vartheta}}_{c}|/{T}_{\mathrm{N}}\ensuremath{\sim}3$, indicates a low level of frustration. The heat-capacity data above ${T}_{\mathrm{N}}$ can be interpreted in terms of a one-dimensional spin-correlation model, as can the low-temperature data which follow a ${T}^{1}$ power law. This is consistent with an earlier suggestion. The difference with isostructural ${\mathrm{Sr}}_{2}\mathrm{Y}\mathrm{Mo}{\mathrm{O}}_{6}$ is attributed to differences in the local distortion of the Mo--O octahedron and the resulting orbital ordering.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.008 | 0.005 |
| Meta-epidemiology (narrow) | 0.006 | 0.011 |
| Meta-epidemiology (broad) | 0.003 | 0.010 |
| Bibliometrics | 0.003 | 0.006 |
| Science and technology studies | 0.007 | 0.009 |
| Scholarly communication | 0.009 | 0.008 |
| Open science | 0.012 | 0.011 |
| Research integrity | 0.009 | 0.009 |
| Insufficient payload (model declined to judge) | 0.521 | 0.015 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; both teacher heads agree on what is shown here.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".