Presentation Title

Croconic Acid Crystallization on Alpha Silica Surface

Faculty Mentor

Dr. Kimberley Cousins

Start Date

18-11-2017 2:15 PM

End Date

18-11-2017 3:15 PM

Location

BSC-Ursa Minor 14

Session

Poster 3

Type of Presentation

Poster

Subject Area

physical_mathematical_sciences

Abstract

Croconic acid (CA) has recently been highly studied due to it being an organic molecule that is a ferroelectric material with high remnant polarization at and above room temperature. In our study of croconic acid on a silica surface, we developed models to explain the fundamental differences in deposition properties on silica, with and without an applied electric field; in particular, needle-like structures that CA forms when an electric field is not applied, while an ordered thin film forms with a strong electric field. We used plane wave density functional theory within the VASP program to calculate surface structures. This was done by first optimizing the alpha silicon oxide surface without CA. Then we modeled the orientation of CA as it binds/adsorbs initially to the surface before the gas-phase CA forms a crystal. With no electric field in the CA-silica system allows for upright oscillation of CA, causing canted needle-like structures. However, an applied electric field on the CA-silica system influences the behavior of CA to maintain a flatter motif in respect to the silica surface. Furthermore, with an applied electric field, the initial orientation will encourage gas-phase CA to form an ordered crystal whose polarization is more aligned, increasing its ferroelectric behavior.

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Nov 18th, 2:15 PM Nov 18th, 3:15 PM

Croconic Acid Crystallization on Alpha Silica Surface

BSC-Ursa Minor 14

Croconic acid (CA) has recently been highly studied due to it being an organic molecule that is a ferroelectric material with high remnant polarization at and above room temperature. In our study of croconic acid on a silica surface, we developed models to explain the fundamental differences in deposition properties on silica, with and without an applied electric field; in particular, needle-like structures that CA forms when an electric field is not applied, while an ordered thin film forms with a strong electric field. We used plane wave density functional theory within the VASP program to calculate surface structures. This was done by first optimizing the alpha silicon oxide surface without CA. Then we modeled the orientation of CA as it binds/adsorbs initially to the surface before the gas-phase CA forms a crystal. With no electric field in the CA-silica system allows for upright oscillation of CA, causing canted needle-like structures. However, an applied electric field on the CA-silica system influences the behavior of CA to maintain a flatter motif in respect to the silica surface. Furthermore, with an applied electric field, the initial orientation will encourage gas-phase CA to form an ordered crystal whose polarization is more aligned, increasing its ferroelectric behavior.