MétaCan
Menu
Back to cohort
Record W2143835618 · doi:10.1039/b712253e

Chiral induction in nematic and smectic C liquid crystal phases by dopants with axially chiral 1,11-dimethyl-5,7-dihydrodibenz[c,e]thiepin cores

2007· article· en· W2143835618 on OpenAlexaff
Matthew P. Thompson, Robert P. Lemieux

Bibliographic record

VenueJournal of Materials Chemistry · 2007
Typearticle
Languageen
FieldMaterials Science
TopicLiquid Crystal Research Advancements
Canadian institutionsQueen's University
Fundersnot available
KeywordsDopantLiquid crystalCrystallographyPhase (matter)ChemistryDopingMaterials scienceStereochemistryOrganic chemistryOptoelectronics

Abstract

fetched live from OpenAlex

Three calamitic molecules with axially chiral cores, (S)-3,9-bis[(4-dodecyloxybenzoyl)oxy]-1,11-dimethyl-5,7-dihydrodibenzo[c,e]thiepin (5a), (R)-3,9-bis[(4-butoxybenzoyl)oxy]-1,11-dimethyl-5,7-dihydrodibenzo[c,e]thiepin (5b), and (R)-3,9-bis[(4-octyloxybenzoyl)oxy]-1,11-dimethyl-5,7-dihydrodibenzo[c,e]thiepin (5c), were synthesized in optically pure form and doped in four calamitic liquid crystal hosts with I–N–SmA–SmC (INAC) phase sequences (PhP, PhB, NCB76 and DFT), and in the nematic host 5CB. Helical twisting powers (β) in the N* phase are in the range of 24–43 µm–1 with the INAC hosts, and in the range of 56–58 µm–1 with 5CB at T–TN-I = –2 K, which are comparable to those previously reported for axially chiral binaphthyls. Interestingly, these dopants were found to stabilize and broaden the temperature range of the N* phase in 5CB. With some of the dopant–INAC host mixtures, the induction of a chiral TGBA* phase was also observed. Dopant 5a induces a measurable spontaneous polarization in the SmC phase of the achiral phenylpyrimidine host PhP, giving a polarization power δp of –104 ± 20 nC cm–2. Comparisons of helical twisting powers in the N* and SmC* phases, and polarization powers in the SmC* phase, for dopants 5a–c and the dinitro analogue (+)-1,11-dinitro-3,9-bis[(4-nonyloxybenzoyl)oxy]-5,7-dihydrodibenzo[c,e]thiepin (4) suggest that the nitro substituents play a dominant role in promoting chirality transfer in the SmC* phase, whereas the helical topography of the core appears to be a more important factor in promoting chirality transfer in the N* phase.

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 imitation

Not 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.

metaresearch head score (Codex)0.003
metaresearch head score (Gemma)0.001
Version: codex-gemma-dda1882f352aValidation status: machine_predicted_unvalidated
Candidate categoriesMeta-epidemiology (narrow)
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Bench or experimental · Consensus signal: Bench or experimental
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.002
Threshold uncertainty score1.000

Codex and Gemma teacher scores by category

CategoryCodexGemma
Metaresearch0.0030.001
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0010.000
Bibliometrics0.0000.000
Science and technology studies0.0000.000
Scholarly communication0.0000.001
Open science0.0000.000
Research integrity0.0000.000
Insufficient payload (model declined to judge)0.0010.000

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.

Opus teacher head0.012
GPT teacher head0.280
Teacher spread0.268 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Classification

machine, unvalidated

Machine predicted; a candidate call from one teacher head, not a consensus.

Study designBench or experimental
Domainnot available
GenreEmpirical

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".

Quick stats

Citations29
Published2007
Admission routes1
Has abstractyes

Explore more

Same venueJournal of Materials ChemistrySame topicLiquid Crystal Research AdvancementsFrench-language works237,207