A TD‐DFT Study on the Effect of Intermolecular Hydrogen Bonding on the Photophysical Properties of N‐Methyl‐1, 8‐naphthalimide. Issue 3 (10th December 2012)

• Record Type: Journal Article
• Authors: Yang, Da‐Peng; Li, Hui; Liu, Yu‐Fang
• Is Part Of: Journal of the Chinese Chemical Society. Volume 60:Issue 3(2013:Mar.)
• Page Start: 267
• Page End: 274
• Publication Date: 2012-12-10
• Subjects: Chemistry -- Periodicals; Electronic journals; 540.5
• DOI: 10.1002/jccs.201200353
• Languages: English
• ISSNs: 0009-4536

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>The effect of intermolecular hydrogen bonding on the photophysical properties of N‐methyl‐1, 8‐naphthalimide (<bold>2</bold>) has been investigated by time‐dependent density functional theory (TD‐DFT) method. The UV and IR spectra of <bold>2</bold> monomer and its hydrogen‐bonded complexes formed with 2, 2, 2‐trifluoroethanol (TFE) <bold>2</bold>+TFE and <bold>2</bold>+2TFE have been calculated, which confirm the presence of intermolecular hydrogen bonding interactions between the carbonyl groups of the aromatic imide and the hydroxyl group of the polyfluorinated alcohol. The absorption and fluorescence intensities going from <bold>2</bold> monomer via hydrogen‐bonded complex <bold>2</bold>+TFE to <bold>2</bold>+2TFE were found to be gradually enhanced with the wavelength gradually red‐shifted. The enhancements of the fluorescence intensities from <bold>2</bold> monomer to hydrogen‐bonded complexes <bold>2</bold>+TFE and <bold>2</bold>+2TFE were attributed to the decrease of the intersystem crossing (ISC) efficiency from the first excited singlet state S₁¹(ππ*) to the second excited triplet state T₂³(nπ*), whose energy was increased relative to its ground state due to the intermolecular hydrogen bonding interactions.</p> </abstract>