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تسجيل مستخدم جديدالثنائي الديشروم الكروي الثنائي الثلاثي الضوئي الإلكتروني
Fourfold Differential Photoelectron Circular Dichroism
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نحن نقدم دراسة مشتركة تجريبية ونظرية للديكرويس الدائري للإشعاع الضوئي (PECD) في ميثيلوكسيران. بالكشف عن الإشعاع الضوئي O 1s في التزام مع الأيونات المفصلة، نحدد توجيه المولايد واتجاه الانبعاث الإشعاعي في الإطار المختبري. وبذلك، نحصل على تباين ديكرويسي رباعي الأبعاد بأكثر من 50٪. يتم تطبيق هذا التشابه الأزواجي القوي على الحسابات الهندسية الإلكترونية بأب إنيتيو. والتي توفر هذا التباين المضيء يجعل PECD للمولايد الأزواجية المثبتة في المساحة أداة أكثر حساسية للتعرف الأزواجي في الغاز.
We report on a joint experimental and theoretical study of photoelectron circular dichroism (PECD) in methyloxirane. By detecting O 1s-photoelectrons in coincidence with fragment ions, we deduce the molecules orientation and photoelectron emission direction in the laboratory frame. Thereby, we retrieve a fourfold differential PECD clearly beyond 50%. This strong chiral asymmetry is reproduced by ab initio electronic structure calculations. Providing such a pronounced contrast makes PECD of fixed-in-space chiral molecules an even more sensitive tool for chiral recognition in the gas phase.
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It is commonly accepted that the magnitude of a photoelectron circular dichroism (PECD) is governed by the ability of an outgoing photoelectron wave packet to probe the chiral asymmetry of a molecule. To be able to accumulate this characteristic asym
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