Vibrational spectroscopy



The Vibrational spectroscopy at the IFG operates various techniques :
We process all IR spectroscopic problems of the institute and support other institutes of the KIT as well as external partners with the development of applications and project accompanying measurements.

Our bandwidth covers simple measurements of main components in solids and liquids with KBr pellet technique and ATR-methods, the investigation of the compounds and order of different thin layer systems and monolayer with grazing incidence spectroscopy and micro imaging methods with high spatial resolution down to 1 micron.

Beside simple instruments for routine and quality control the equipment consists of several spectrometers for high end applications. Hereby special attention is turned to the investigation of interfaces.

We’re carrying out special measurements for characterizations of thin layers down to monolayers (nm) as well as imaging-(2 & 3D) infrared and Raman microscopy. In addition we’re operating an FITR spectrometer specially optimized for lifescience applications (e.g. conformational analyses of proteins).


Overview of our applications at IFG and for other KIT institutes:

 

  • IRRAS spectroscopy in grazing incidence under variable angle (polarized) for the characterization of molecular layers on gold and dielectric substrates. In combination with ATR this technique is applied for the investigation of the liquid/solid (air/water) interface.


  • ATR spectroscopy with conventional (ZnSe, Ge and diamond, single and multiple reflection, membrane and liquid cells) and functionalized crystals for in situ and kinetic measurements for reaction monitoring of interfaces on molecular scale and investigations of biological material like single cells or biofilms.


  • Diffuse reflectance (DRIFT) spectroscopy for measurements of strong scattering and opaque samples.


  • Rapid- and stepscan technique for time resolved measurements and - in association with photoaccoustic spectroscopy - depth profiling.


  • IR- und Raman microscopy for determination of small particles and structures


  • IR- and Raman- microscopy for 3D imaging with high spatial resolution (1µm) -in combination with confocal Raman as well for depth profiling of transparent samples


  • Raman investigations with high temperature heating stage up to 1500°C

 

 

Examples for applications:

 

MolsSpek01_EN

Silane Hydrolysis from solution to surface: Visualisation of the formation of a silane layer on a SiO2 surface (Si Substrate)



MolSpek02_EN

IRRA - Spectra of C18SiCl3-SAM on SiO2 (left) and C18SiCl3 on Si3N4 (right). Spectra were aquired for each SAM with s- and p- polarizded light under diffrent angles of incidence. The used substrates are IR-transperent!

 

MolSpek03_DE

IR-Imaging of structured MOF on gold substrate. 3D (left) and 2D (right) signal image of the COO-stretching vibration (1510-1780cm-1) which is correlated to the endstanding function of the deposited MOF. The size of the written structure is between 6 and 10µm2

 

Our expertise and experience is provided to all other institutes/units of the KIT and to external partners.