Photochemistry of the α-Al₂O₃-PETN Interface

Roman V Tsyshevsky; Anton Zverev; Anatoly Mitrofanov; Sergey N Rashkeev; Maija M Kuklja

doi:10.3390/molecules21030289

Photochemistry of the α-Al₂O₃-PETN Interface

Molecules. 2016 Feb 29;21(3):289. doi: 10.3390/molecules21030289.

Authors

Roman V Tsyshevsky¹, Anton Zverev^{2

3}, Anatoly Mitrofanov^{4

5}, Sergey N Rashkeev^{6

7}, Maija M Kuklja⁸

Affiliations

¹ Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA. rtsyshev@umd.edu.
² Department of Organic and Physical Chemistry, Kemerovo State University, Kemerovo 650043, Russia. anthon.zverev@yandex.ru.
³ Yurga Institute of Technology, National Research Tomsk Polytechnic University, Yurga 652057, Russia. anthon.zverev@yandex.ru.
⁴ Department of Organic and Physical Chemistry, Kemerovo State University, Kemerovo 650043, Russia. anatoly.y.mitrofanov@gmail.com.
⁵ Yurga Institute of Technology, National Research Tomsk Polytechnic University, Yurga 652057, Russia. anatoly.y.mitrofanov@gmail.com.
⁶ Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA. rashkesn@yahoo.com.
⁷ Qatar Environment & Energy Research Institute, Hamad Bin Khalifa University, Qatar Foundation, P.O. Box 5825, Doha, Qatar. rashkesn@yahoo.com.
⁸ Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA. mkukla@nsf.gov.

Abstract

Optical absorption measurements are combined with electronic structure calculations to explore photochemistry of an α-Al₂O₃-PETN interface formed by a nitroester (pentaerythritol tetranitrate, PETN, C₅H₈N₄O12) and a wide band gap aluminum oxide (α-Al₂O₃) substrate. The first principles modeling is used to deconstruct and interpret the α-Al₂O₃-PETN absorption spectrum that has distinct peaks attributed to surface F⁰-centers and surface-PETN transitions. We predict the low energy α-Al₂O₃ F⁰-center-PETN transition, producing the excited triplet state, and α-Al₂O₃ F⁰-center-PETN charge transfer, generating the PETN anion radical. This implies that irradiation by commonly used lasers can easily initiate photodecomposition of both excited and charged PETN at the interface. The feasible mechanism of the photodecomposition is proposed.

Keywords: F-centers; decomposition barrier; electronically excited and charged state; explosives; initiation of detonation; oxygen vacancy; singlet-triplet exciton.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Aluminum Oxide / chemistry*
Models, Molecular
Pentaerythritol Tetranitrate / chemistry*
Photochemical Processes*
Photochemistry

Substances

Pentaerythritol Tetranitrate
Aluminum Oxide