Structure of the Ethylammonium Nitrate Surface: An X-ray Reflectivity and Vibrational Sum Frequency Spectroscopy Study

• DOI: 10.1021/la904697g
• Publication Date: 2010-03-19T19:37:06Z
• Authors: Petru Niga; Deborah Wakeham; Andrew Nelson; Gregory G. Warr; Mark Rutland; Rob Atkin
• Keywords: vibrational sum frequency; air interface; spectroscopy; Nitrates; ethylammonium nitrate (EAN); X-ray reflectivity; 02 engineering and technology; Reflectivity; 01 natural sciences; 0104 chemical sciences; Symmetry; X-ray spectroscopy; Vibrational states; 0210 nano-technology; Molecular structure

X-ray reflectivity and vibrational sum frequency spectroscopy are used to probe the structure of ethylammonium nitrate (EAN)−air interface. reveals that EAN−air interface is structured consists alternating nonpolar charged layers extend 31 Å into bulk. Vibrational interfacial cations have their ethyl moieties oriented toward air, with CH3 C3 axis positioned ∼36.5° from normal. This invariant between 15 51 °C. On account its molecular symmetry, orientation anion cannot be determined certainty.