title: Broadband femtosecond circular dichroism spectrometer with white-light polarization control.
abstract: A broadband, femtosecond transient circular dichroism (TRCD) spectrometer has been developed and tested in the wavelength range from 350 to 700 nm. The spectrometer uses a femtosecond probe white light with well-defined circular polarization. The latter is modulated by the polarization of a narrowband seed pulse. We have implemented a dual-beam probe geometry with phase-locked detection technique to increase the signal-to-noise ratio and to reduce optical artifacts. The spectrometer allows the acquisition of TRCD spectra with subpicosecond time resolution and typical noise levels of 10(-4) absorbance units. The performance of this instrument has been demonstrated on bis(merocyanine) nanorod aggregates in tetrahydrofurane/methylcyclohexane solution. The case study confirmed that this spectrometer is effective for the investigation of chiral properties in various molecular and nanostructural systems that have transient spectra in the UV-visible spectral range.
authors.affiliation: Eugene F. Merkert Chemistry Center, Boston College, 2609 Beacon St., Chestnut Hill, Massachusetts 02467, USA.
authors.forename: Anton
authors.initials: A
authors.lastname: Trifonov
authors.forename: Ivan
authors.initials: I
authors.lastname: Buchvarov
authors.forename: Andreas
authors.initials: A
authors.lastname: Lohr
authors.forename: Frank
authors.initials: F
authors.lastname: Würthner
authors.forename: Torsten
authors.initials: T
authors.lastname: Fiebig
mesh_terms: D000042:Absorption; D016477:Artifacts; D001578:Benzopyrans / Q000737:chemistry; D002942:Circular Dichroism / Q000295:instrumentation*; D003510:Cyclohexanes / Q000737:chemistry; D004867:Equipment Design; D005663:Furans / Q000737:chemistry; D007211:Indoles / Q000737:chemistry; D008027:Light; D043942:Nanotubes / Q000737:chemistry; D055095:Optics and Photonics / Q000295:instrumentation; D012996:Solutions / Q000737:chemistry; D013057:Spectrum Analysis / Q000295:instrumentation*; D013997:Time Factors
chemical_list: D001578:Benzopyrans; D003510:Cyclohexanes; D005663:Furans; D007211:Indoles; D012996:Solutions; C548873:merocyanine; C521475:methylcyclohexane