C60 ((+) が2つの拡散星間帯の媒介体であることの実験室での確認
E K Campbell1, M Holz1, D Gerlich2
1Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland.
Nature
|July 17, 2015
まとめ
研究者達は 星間波帯を拡散させる 分子を特定しました 実験室のスペクトロスコピーは,バックミンスターフルレンのイオン (C60+) が星間ガスで特定の吸収線を生成することを確認した.
科学分野:
- 天体化学
- スペクトロスコーピー
- 天体物理学
背景:
- 拡散星間帯 (DIB) は,赤くした星のスペクトルで見られる未確認の吸収線である.
- 以前の研究では,マトリックス分離実験に基づいて,DIBの2つの潜在的なキャリアとしてバックミンスターフルレンイオン (C60+) が示唆されました.
研究 の 目的:
- C60+が9,632と9,577アングストロームの星間波帯を運ぶものであることを確認する.
- 天文観測と直接比較するために,C60+のガス相吸収スペクトルを取得する.
主な方法:
- C60+の実験室ガス相スペクトロスコーピーを実施した.
- 星間条件をシミュレートするためにC60+イオンを5.8ケルビンまで冷却した.
- 吸収スペクトルが測定され,分析された.
主要な成果:
- ガス相C60+の実験用スペクトルは,最大吸収値を9,632.7 ± 0.1アングストロームと9,577.5 ± 0.1アングストロームで示した.
- 測定された波長と帯域プロファイルは,以前に観測された拡散した星間帯域と密接に一致します.
- 半最大の全幅は2.2 ± 0.2 Ångströmsと2.5 ± 0.2 Ångströmsと決定された.
結論:
- 9,632 と 9,577 の星間波帯は,C60+ から生じたものとして決定的に識別されている.
- この発見は 実験室での測定と 星間分子に関する天文学的観測との 重要なつながりを提供します
- C60+がDIBsの媒介者であることが判明したことで,星間化学と星間媒体の構成に関する理解が進んでいます.
関連する概念動画
Atomic Emission Spectroscopy: Interference
755
In atomic emission spectroscopy (AES), high-temperature atomizers excite a broad range of elements and molecules that generate complex emissions from sources such as oxides, hydroxides, and flame combustion products in the flame or plasma. Several strategies can be employed to minimize spectral interferences caused by overlapping emission lines or bands. These include increasing instrument resolution, choosing alternative emission lines, optimally placing the detector in low-background regions,...
755
Atomic Emission Spectroscopy: Lab
817
AES is a powerful analytical technique, especially effective when used with plasma sources, producing abundant spectra in characteristic emission lines. The Inductively Coupled Plasma (ICP), in particular, yields superior quantitative analytical data due to its high stability, low noise, low background, and minimal interferences under optimal experimental conditions. However, newer air-operated microwave sources are emerging as promising alternatives that could be more cost-effective than...
817
¹³C NMR: ¹H–¹³C Decoupling
2.1K
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...
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
2.1K
UV–Vis Spectroscopy: Woodward–Fieser Rules
29.7K
UV–Visible absorption spectra of conjugated dienes arise from the lowest energy π → π* transitions. The light-absorbing part of the molecule is called the chromophore, and the substituents directly attached to the chromophore are called auxochromes. A strong correlation exists between the absorption maxima, λmax, and the structure of a conjugated π system. The Woodward–Fieser rules predict the value of λmax for a given structure by adding the...
29.7K
UV–Vis Spectroscopy of Conjugated Systems
9.2K
Organic compounds with conjugated double bonds show strong absorption features in the UV–visible region of the electromagnetic spectrum attributed to π → π* electronic excitations. Generally, a UV–vis absorption spectrum is recorded as a plot of absorbance vs wavelength. The wavelength of maximum absorbance, which manifests as a peak in the absorption spectrum, is denoted as λmax.
One of the factors influencing λmax is the extent of conjugation in...
One of the factors influencing λmax is the extent of conjugation in...
9.2K
¹H NMR: Complex Splitting
2.2K
A proton M that is coupled to a proton X results in doublet signals for M. However, NMR-active nuclei can be simultaneously coupled to more than one nonequivalent nucleus. When M is coupled to a second proton A, such as in styrene oxide, each peak in the doublet is split into another doublet.
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied...
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied...
2.2K


