Spec, Thermal, and X-ray Facility
Absorption of light in the 4000 to 400 cm-1 range is used to identify functional groups in molecules due to peaks occurring at characteristic frequencies.
Available Instrumentation:- Perkin Elmer 1760 Infrared spectrometer with the following accessories:
- Spectra-Tech IR Plan microscope
- Diffuse reflectance (DRIFT)
- Horizontal attenuated total reflectance (HATR)
- Multiple internal reflection (MIR) accessories
- Detectors include both TGS and MCT
- Zeiss Stemi 2000 stereomicroscope
- Mattson Alpha Centauri Infrared Spectrometer Applications of Fourier Transform - Infrared
- General Infrared
- Characterization of chemicals
- Quantitative analysis of known compound in mixtures
- Aid in determining structure of unknown
- Microscope (used when microsampling is required)
- Identify contaminants
- Examine multi-layered laminates
- Examine coatings and films
- Surface defects
- Diffuse Reflectance
- Analyze powders directly without making pellets
- Horizontal Attenuated Total Reflectance
- Characterization of liquids, pastes or compressible powders, films or solids
- Multiple Internal Reflection
- Characterization of thin films
Absorption of light in the 190 to 820 nm range can be used to determine or follow the concentration of molecules containing conjugated systems.
Available Instrumentation:- Hewlett Packard 8452A Diode Array Spectrophotometer with the following
accessories:
- magnetic stirrer
- temperature control
- data station
- Spectral range = 190 - 820 nm at a maximum range of 1 scan/0.1 sec.
- General survey scans for qualitative analysis
- Reaction kinetics using single to full wavelength range
- Quantitative analysis of single or multiple components
The emission of electromagnetic radiation from an excited singlet state of a molecule to its corresponding ground singlet state. The technique exhibits superb detection limits (to "single molecule levels" with a laser and proper optics) and provides information about the photophysics of the emitting species and/or the local environment surrounding the fluorescence center.
Available Instrumentation:- SLM 8100 spectrofluorometer with a wavelength range of 200-900 nm. The spectral resolution is adjustable from 0.25-32 nm. The system is capable of the following basic experiments:
- Steady-state excitation and emission scanning as well as synchronous scanning
- Fixed wavelength intensity acquisitions
- Time-dependent intensity data for ms or slower kinetic experiments
- Steady-state polarization/anisotropy experiments
- Determine fluorophore concentration
- Polycyclic aromatic hydrocarbon screening
- Determining excitation and emission profiles for unknown or new fluorophores and phosphors that may be applied as new probes, sensor elements, or photodynamic therapy agents
- Quantum yield determinations
- Probing the local environment surrounding the fluorophore (pH, dipolarity, mobility)
- Protein-protein interactions
- Vesicles
- Forster energy transfer
- Host-guest/protein-ligand binding studies and binding equilibria
- Polarization immunoassay
- Enzyme kinetics
- High-pressure (hydrostatic) experiments to 3 kbar
- Solid-surface luminescence
Thermal analysis is used for the characterization of materials by monitoring changes in physical or thermal properties as a function of time and temperature. They are often used to certify product quality of plastics, thermoset materials, foods, and elastomers.
Differential Scanning Calorimeter:Measures energy flow and temperature associated with chemical reactions or changes in physical state.
Available Instrumentation:- Perkin Elmer DSC-7 with:
- Drybox
- Liquid N2 cooling, temperature range is -170°C to 725°C.
- Normal sample size is 0.5 to 30 mg
- Melting point
- Glass transition temperature
- Kinetics
- Specific heat
- Degree of cure
- Study of chemical reactions/state changes
Used to study process where weight changes as a function of time or temperature.
Available Instrumentation:- Perkin Elmer TGA 7
- The temperature range is room temperature to 1000°C
- The balance sensitivity is 0.1 mg and the sample size is 2 to 50 mg
- Water or volatile content
- Temperature dependent chemical reactions (loss of CO2 etc.)
- Decomposition temperature/limit of stability
- Component quantitation in mixtures
- Quantitation of fillers and reinforcing agents in plastics
- Curie print measurements
We are equipped with an APEX II Bruker diffractometer for X-ray diffraction data collection on single crystals. Final information will include the following:
- Table of information on X-ray diffraction experiment, including unit cell, space group, reflections collected, agreement indices etc.
- Table of atomic coordinates.
- Table of bond lengths.
- Table of anisotropic displacement parameters.
- Table of positions of hydrogen atoms.
- Illustration of molecular geometry. Other information - torsional angles, least-squares planes, packing of molecules in the crystal - may be obtained upon request. Size of crystals required - ideally about 0.3 mm in all three dimensions for a typical organic compound; smaller for crystals containing heavier elements.
- Crystallographic Information File (CIF)
For help in designing appropriate experiments, please contact:
Professor Philip Coppens
(716) 645-6800 ext. 2217
Email: coppens@buffalo.edu