Solvatochromic Study of the Microenvironment of Surface-bound Spiropyrans

Rohit Rosario, Devens Gust, Mark Hayes, Joseph Springer, Antonio Garcia

Research output: Contribution to journalArticlepeer-review

81 Scopus citations


Spiropyrans are a group of organic molecules that undergo a reversible photoinduced transformation (i.e., photochromism) from a colorless, nonplanar spiropyran form to a colored, planar merocyanine form. Photochromism is accompanied by a large change in the structure and in the dipole moment. These changes suggest that such molecules might be useful in light-controlled, "smart surface" applications. This study examines the effect of the microenvironment near the surface-bound spiropyran on its photochemistry. The surfaces were designed to exhibit a mixture of hydrophobic and hydrophilic components by using a mixed silane chemistry on a glass substrate, and the spiropyran was covalently bound to the surface via amide linkages. The solvatochromic behavior of spiropyran derivatives was studied in solution using UV-vis absorption spectroscopy and fluorescence spectroscppy for comparison with the surface-bound species. Spiropyrans in solution and on the surface both exhibited negative solvatochromism. Correlations between emission maxima of the Spiropyrans and Reichardt's ET(30) polarity scale revealed that the surface-bound spiropyran experienced lower polarity than a solution model in solvents of low and medium polarities. Linear solvation energy relationships using the Kamlet-Taftpolarity scales showed that hydrogen bonding played a prominent role in solvent stabilization of surface-bound spiropyrans in hydrogen-bonding solvents. The surface design used causes the spiropyran to interact significantly with the surface in solvents of lower polarity and to behave as if it were dissolved in solution in more polar, hydrogen-bonding solvents.

Original languageEnglish (US)
Pages (from-to)8801-8806
Number of pages6
Issue number21
StatePublished - Oct 14 2003

ASJC Scopus subject areas

  • General Materials Science
  • Condensed Matter Physics
  • Surfaces and Interfaces
  • Spectroscopy
  • Electrochemistry


Dive into the research topics of 'Solvatochromic Study of the Microenvironment of Surface-bound Spiropyrans'. Together they form a unique fingerprint.

Cite this