Jove
Visualize
お問い合わせ
JoVE
x logofacebook logolinkedin logoyoutube logo
JoVEについて
概要リーダーシップブログJoVEヘルプセンター
著者向け
出版プロセス編集委員会範囲と方針査読よくある質問投稿
図書館員向け
推薦の声購読アクセスリソース図書館諮問委員会よくある質問
研究
JoVE JournalMethods CollectionsJoVE Encyclopedia of Experimentsアーカイブ
教育
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab Manual教員リソースセンター教員サイト
利用規約
プライバシーポリシー
ポリシー

関連する概念動画

π Electron Effects on Chemical Shift: Overview01:27

π Electron Effects on Chemical Shift: Overview

1.1K
An applied magnetic field causes loosely bound π-electrons in organic molecules to circulate, producing a local or induced diamagnetic field over a large spatial volume. As the molecules tumble in solution, the field generated by π-electrons in spherical substituents results in a zero net field. However, the net field generated by π-electrons in non-spherical substituents is not zero. The effect of this induced field depends on the orientation of the molecule with respect to B0,...
1.1K
Diamagnetic Shielding of Nuclei: Local Diamagnetic Current01:14

Diamagnetic Shielding of Nuclei: Local Diamagnetic Current

960
An applied magnetic field causes the electrons present in the molecule to circulate, setting up a local diamagnetic current within the molecule. The local diamagnetic current arising from circulating sigma-bonding electrons induces a magnetic field, Blocal that opposes the applied magnetic field, B0. The effective magnetic field experienced by these nuclei is given by the difference between the applied and local magnetic fields in a phenomenon called local diamagnetic shielding. Essentially,...
960
¹³C NMR: ¹H–¹³C Decoupling01:04

¹³C NMR: ¹H–¹³C Decoupling

1.2K
The probability of having two carbon-13 atoms next to each other is negligible because of the low natural abundance of carbon-13. Consequently, peak splitting due to carbon-carbon spin-spin coupling is not observed in spectra. However, protons up to three sigma bonds away split the carbon signal according to the n+1 rule, resulting in complicated spectra.
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
1.2K
π Electron Effects on Chemical Shift: Aromatic and Antiaromatic Compounds01:14

π Electron Effects on Chemical Shift: Aromatic and Antiaromatic Compounds

1.3K
In aromatic compounds, such as benzene, the circulation of (4n + 2) π-electrons sets up a diamagnetic or diatropic ring current around the perimeter of the molecule. This current induces a magnetic field that opposes the external field inside the ring and reinforces it on the outside. The protons in benzene are deshielded and exhibit high chemical shifts in the range 6.5–8.5 ppm. The shielding effect at the center of the ring is evident in complex aromatic molecules, such as...
1.3K
Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)01:20

Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)

1.1K
Two NMR-active nuclei bonded to a central atom can be involved in geminal or two-bond coupling. Geminal coupling is commonly seen between diastereotopic protons in chiral molecules and unsymmetrical alkenes, among others.
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
1.1K
¹H NMR: Interpreting Distorted and Overlapping Signals01:02

¹H NMR: Interpreting Distorted and Overlapping Signals

1.1K
Spin systems where the difference in chemical shifts of the coupled nuclei is greater than ten times J are called first-order spin systems. These nuclei are weakly coupled, and their chemical shifts and coupling constant can generally be estimated from the well-separated signals in the spectrum.
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...
1.1K

こちらも読む

関連記事

共著者、ジャーナル、引用グラフによってこの研究に関連する記事。

並び替え
Same author

Reversible Regulation of Thermal Conductivity through Spin-Crossover Transitions.

Journal of the American Chemical Society·2026
Same author

Author Correction: Bose-Einstein condensation of a two-magnon bound state in a spin-1 triangular lattice.

Nature materials·2026
Same author

Uncovering complex phonon interactions in Mg<sub>3</sub>Bi<sub>2-x</sub>Sb<sub>x</sub>: topology and avoided crossings.

Nature communications·2026
Same author

Calcium-phosphate bridge is a novel phosphorylation switch that stabilises protein-complexes during HIV assembly.

bioRxiv : the preprint server for biology·2026
Same author

Publisher Correction: Bose-Einstein condensation of a two-magnon bound state in a spin-1 triangular lattice.

Nature materials·2025
Same author

Bose-Einstein condensation of a two-magnon bound state in a spin-1 triangular lattice.

Nature materials·2025
Same journal

Correction to "Living Therapeutic Microneedles Integrated with Built-In Metabolic Engines for Autonomous Diabetic Wound Management".

Nano letters·2026
Same journal

Chiral Quasi-Bound States in the Continuum on the Verge of the Light Cone.

Nano letters·2026
Same journal

Scalable Atomically Interfaced Heterostructure Photoelectrodes for Broadband Solar Energy Harvesting and Stable Li-Ion Storage.

Nano letters·2026
Same journal

Bulk and Surface Excitons in the van der Waals Magnet CrSBr: Magneto-Optical Studies to 55 T.

Nano letters·2026
Same journal

High-Entropy Alloy Nanomaterials with Well-Designed Nanostructures for Electrocatalytic Applications.

Nano letters·2026
Same journal

Symmetrical Tetravalent Aptamer-Protein Conjugate with Ultrahigh <i>In Vivo</i> Stability for Targeted Cancer Imaging and Therapy.

Nano letters·2026
関連記事をすべて見る

関連する実験動画

Updated: Sep 10, 2025

Characterization of Nanocrystal Size Distribution using Raman Spectroscopy with a Multi-particle Phonon Confinement Model
06:54

Characterization of Nanocrystal Size Distribution using Raman Spectroscopy with a Multi-particle Phonon Confinement Model

Published on: August 22, 2015

13.7K

ナノダイアモンドフォノンに対するマトリックス埋め込み効果

Caleb Stamper1, David L Cortie1,2, Abdulhakim Bake1

  • 1School of Physics and Institute for Superconducting and Electronic Materials, University of Wollongong, Wollongong, NSW 2500, Australia.

Nano letters
|August 20, 2025
PubMed
まとめ
この要約は機械生成です。

ダイヤのナノ結晶をチンのテルリドマトリックスに埋め込むと フォノンスペクトルが変化し,表面フォノンが消し,コアフォノンが柔らかくなる. これらの発見は,ナノ結晶複合材料の性質の理解に影響を与えます.

キーワード:
複合材料ナノクリスタルナノダイアモンド中性子フォノン熱性

さらに関連する動画

Characterization of Ultra-fine Grained and Nanocrystalline Materials Using Transmission Kikuchi Diffraction
09:13

Characterization of Ultra-fine Grained and Nanocrystalline Materials Using Transmission Kikuchi Diffraction

Published on: April 1, 2017

13.7K
Resonance Raman Spectroscopy of Extreme Nanowires and Other 1D Systems
07:44

Resonance Raman Spectroscopy of Extreme Nanowires and Other 1D Systems

Published on: April 28, 2016

15.2K

関連する実験動画

Last Updated: Sep 10, 2025

Characterization of Nanocrystal Size Distribution using Raman Spectroscopy with a Multi-particle Phonon Confinement Model
06:54

Characterization of Nanocrystal Size Distribution using Raman Spectroscopy with a Multi-particle Phonon Confinement Model

Published on: August 22, 2015

13.7K
Characterization of Ultra-fine Grained and Nanocrystalline Materials Using Transmission Kikuchi Diffraction
09:13

Characterization of Ultra-fine Grained and Nanocrystalline Materials Using Transmission Kikuchi Diffraction

Published on: April 1, 2017

13.7K
Resonance Raman Spectroscopy of Extreme Nanowires and Other 1D Systems
07:44

Resonance Raman Spectroscopy of Extreme Nanowires and Other 1D Systems

Published on: April 28, 2016

15.2K

科学分野:

  • 材料科学
  • 凝縮物質物理学
  • ナノテクノロジー

背景:

  • ナノ結晶の格子ダイナミクスは独特ですが,マトリックスに埋め込まれた場合の理解は少ないです.
  • マトリックス埋め込み時のフォノンスペクトルの変化を調査することは,複合材料にとって極めて重要です.

研究 の 目的:

  • タンテルリドマトリックスに埋め込む前と後のダイヤモンドナノ結晶のフォノンスペクトルを体系的に比較する.
  • ナノクリスタル表面とコアフォノンダイナミクスのマトリックスエンベディングの影響を調査する.

主な方法:

  • 重いマトリックス内の軽いナノ結晶のフォノンスペクトル (0.5-250 meV) を測定するための飛行時間ニュートロンスペクトル.
  • スペクトル変化の解釈のための古典的な分子動力学シミュレーション.

主要な成果:

  • ダイヤのナノ結晶を亜鉛 Telluride マトリックスに埋め込むと,表面フォノンが消し,コアフォノンが柔らかくなる.
  • フォノン線の幅は,マトリックス誘発の境界条件と牽引力により狭くなります.
  • アンハーモニックな表面のダイナミクスは抑制され,集積されたナノダイアモンドと孤立したナノダイアモンドの間で変化が観察されます.

結論:

  • マトリックス埋め込みはナノクリスタル格子ダイナミクスを大きく変化させます
  • 観測された変化は,ナノ複合材料,特に熱電学的物質の振動および熱力学的性質を最適化するために重要です.