title: Refined Insights in the Photochromic spiro-Dihydroindolizine/Betaine System.
abstract: We have revisited the photochromic spiro-dihydroindolizine/betaine system by comparing state-of-the-art density functional theory calculations with experimental data. Time-dependent density functional theory calculations are employed to examine the transformations occurring after photoexcitation. This study confirms that photoexcitation of the spiro-dihydroindolizine leads to the formation of the cis-betaine. However, isomerization to the trans-betaine follows through a complicated and formerly unknown potential energy landscape, which consists of a network of transition states and intermediates. The available pathways across this potential energy landscape will determine the kinetics of the forward reaction from the cis-betaine to the trans-betaine and then, even more importantly, the back-reaction. Virtually all practical applications of this optical switch rely on these reactions and, therefore, occur within this landscape. Predicting the network of transition states and intermediates for substituted spiro-dihydroindolizine/betaine systems will enable the in-silico design of optical switches with enhanced performance.
authors: Department of Chemistry, Kansas State University , 213 CBC Building, Manhattan, Kansas 66506, United States.
authors: Amendra
authors: A
authors: Fernando
authors: Department of Chemistry, Kansas State University , 213 CBC Building, Manhattan, Kansas 66506, United States.
authors: Aruni P
authors: AP
authors: Malalasekera
authors: Department of Chemistry, Kansas State University , 213 CBC Building, Manhattan, Kansas 66506, United States.
authors: Jing
authors: J
authors: Yu
authors: Department of Chemistry, Kansas State University , 213 CBC Building, Manhattan, Kansas 66506, United States.
authors: Tej B
authors: TB
authors: Shrestha
authors: Department of Chemistry, Kansas State University , 213 CBC Building, Manhattan, Kansas 66506, United States.
authors: Emily J
authors: EJ
authors: McLaurin
authors: Department of Chemistry, Kansas State University , 213 CBC Building, Manhattan, Kansas 66506, United States.
authors: Stefan H
authors: SH
authors: Bossmann
authors: Department of Chemistry, Kansas State University , 213 CBC Building, Manhattan, Kansas 66506, United States.
authors: Christine M
authors: CM
authors: Aikens