title: Back-surface gold mirrors for vibrationally resonant sum-frequency (VR-SFG) spectroscopy using 3-mercaptopropyltrimethoxysilane as an adhesion promoter.
abstract: Back-surface mirrors are needed as reference materials for vibrationally resonant sum-frequency generation (VR-SFG) probing of liquid-solid interfaces. Conventional noble metal mirrors are not suitable for back-surface applications due to the presence of a metal adhesion layer (chromium or titanium) between the window substrate and the reflective metal surface. Using vapor deposited 3-mercaptopropyltrimethoxysilane (MPTMS) as a bi-functional adhesion promoter, gold mirrors were fabricated on fused silica substrates. These mirrors exhibit excellent gold adhesion as determined by the Scotch(®) tape test. They also produce minimal spectroscopic interference in the C-H stretching region (2800-3000 cm(-1)), as characterized by VR-SFG. These mirrors are thus robust and can be used as back-surface mirrors for a variety of applications, including reference mirrors for VR-SFG.
authors.affiliation: Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, USA.
authors.forename: Arthur D
authors.initials: AD
authors.lastname: Quast
authors.forename: Feng
authors.initials: F
authors.lastname: Zhang
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Linford
authors.forename: James E
authors.initials: JE
authors.lastname: Patterson