Odd–Even Effects in Electroactive Self-Assembled Monolayers Investigated by Electrochemical Surface Plasmon Resonance and Impedance Spectroscopy
Bibliographic record
Abstract
Subtle conformational-based distinctions in the supramolecular structure of self-assembled monolayers (SAMs) of ω-ferrocenylalkanethiolates on gold (FcC n SAu) have been shown to significantly impact their electrical and redox properties. We investigate the effect of differences in the intermolecular van der Waals interactions and molecular packing energy of FcC n SAu SAMs comprised of an odd (SAM odd ) versus even (SAM even ) number of methylenes on the electrochemical behavior for n = 6–16. Redox-induced thickness changes are investigated by electrochemical surface plasmon resonance (ESPR). Electrochemical impedance spectroscopy (EIS) under non-Faradaic conditions is used to evaluate the dielectric properties of the reduced (neutral) state of the FcC n SAu SAMs. Oxidation of the SAM-bound ferrocenes yields an effective film thickness change of 0.19 ± 0.01 nm, which is attributed to untilting of the alkyl chains. The SAMs manifest odd–even differences in the apparent redox potential, and hence in the thermodynamics of the redox reaction, across the chain lengths n = 6–16 investigated. By contrast, odd–even alternations in the oxidation-induced resonance angle change measured by ESPR and SAM double-layer capacitance determined by EIS are only observed beginning at n = 9 or 10. We show that the odd–even effects in the resonance angle and SAM capacitance are related to a difference in the dielectric constants of SAM odd and SAM even . The chain length dependencies of the measured parameters are discussed in the context of the SAM structure.
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 | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
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.
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; a candidate call from one teacher head, not a consensus.
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".