H + + H2 (v=0, j=0-3)  H2 + +H (v=0-2, j=0) Reaksiyonunun Kuasiklasik Yörünge Metodu İle İncelenmesi

Year 2013, Volume: 2 Issue: 1, 1 - 11, 20.06.2013

İskender Muz , Niyazi Bulut

Abstract

Bu çalışmada H3+ potansiyel enerji yüzeyi üzerinde H++H2H2++H reaksiyonu kuasiklasik yörünge metodu kullanılarak reaksiyondinamikleri ve kinetikleri incelendi. Bu anlamda toplam açısal momentum kuantum sayısının sıfır ve sıfırdan büyük bazı değerleriiçin reaksiyon ihtimaliyetleri ve reaksiyon tesir kesitleri çarpışma enerjisinin fonksiyonu olarak hız sabitleri ise sıcaklığa bağlıolarak hesaplandı. Sonuçlar, giriş kanalındaki iki atomlu H2 molekülünün v=0, j=0 başlangıç kuantum durumundan, ürün molekülünv' = 0 titreşim kuantum durumuna reaksiyon ihtimaliyeti b=0 için bir eşik davranışı sergilemediğini göstermektedir. Bununla birlikteürün molekülün titreşim kuantum sayısı arttıkça reaksiyon ihtimaliyetlerinin bir eşik davranışı gösterdiği ve eşik enerjisi ürünmolekülün titreşim kuantum sayısının artması ile büyük enerji değerlerine doğru kaymakta olduğu görülmektedir. Buna göreH++H2H2++H reaksiyonunun termonötral bir reaksiyon olduğu söylenebilir. Hız sabitleri için 200-1000 0K sıcaklık aralığında birArhenus davranışı sergilememektedir. Bu çalışmada rapor edilen klasik sonuçlar ile kuantum mekaniksel sonuçların birbirleriyleuyum içerisinde olduğu görülmüştür.

Keywords

Reaksiyon ihtimaliyeti, reaksiyon tesir kesiti, hız sabiti, potansiyel enerji yüzeyi, hidrojen

The Investigation of H + + H2 (v=0, j=0-3)  H2 + +H (v=0-2, j=0) Reaction with Quasiclassical Trajectory Method

Abstract

In this study, the reaction dynamics and kinetics have investigated the H+ +H  H + +H reaction on the potential energy surface of H + using the quasi-classical trajectory methods. The reaction probabilities, reaction cross section as a function of collision energy and rate constants depending on temperature have been calculated for total angular momenta J from 0 to 3. The results shown that there isn‟t a threshold behaviour the reaction probability from v=0, j=0 initial quantum state of H molecule‟s in the reactant channel to v' = 0 vibrational quantum states of the H+ molecule in the product channel for b=0. However, as the vibrational quantum number of product molecule increases, the reaction probabilities exhibit a threshold behaviour and product molecule‟s energy shifts toward larger values of energy. Accordingly, the H+ +H  H + +H reaction is a reaction thermo-neutral. The rate constants shown that there isn‟t an Arrhenius type behaviour in range temperature from 200 K to 1000 K. In this study, the results reported that classical and quantum mechanical results were found to be in harmony with each other.

Keywords

Reaction probability, reaction cross section, rate constant, potential energy surface, hydrogen

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