Scientific Glossary
- Perfluoroether: An inert, nontoxic hydrocarbon liquid.
- Phonon: A quantum mechanical vibrational motion with particlelike properties found in solids.
- Photodetachment: The process of detaching an electron from a negative ion with light.
- Photodissociation: The splitting of a molecule by one or more photons.
- Photoelectron spectroscopy: Technique that uses photoionization and analysis of emitted photoelectrons to study the composition and electronic state of a sample.
- Photofragmentation spectrometer: Three-stage instrument that uses an electrospray ion source, a coolable ion trap, mass selection and laser light illumination, and a time-of-flight spectrometer to study solvation processes.
- Photoionization: ion formation due to photon absorption.
- Photoproduct: The product of a chemical reaction caused by light.
- Photovoltaic array: A flat solar panel containing connected solar cells.
- Picosecond: One trillionth of a second.
- Plasma: Hot, ionized gas.
- Porphyrin: An organic compound with four pyrrole rings and a metal cofactor found in biomolecules such as hemoglobin, chlorophyll, and certain enzymes.
- Primary atomic resonance: A natural resonance frequency of an atom that can be excited by a particular frequency of electromagnetic radiation to alter its state and cause fluorescence.
- Pulse shaping: The use of devices such as prisms or gratings to control the spectral phase of a ultrashort laser pulse.
- Pump-probe: The use of two sequential laser pulses to probe atoms, molecules or more complex systems.
- Pyrrole: An aromatic organic compound consisting of a ring of four carbon atoms and a nitrogen atom with five hydrogen atoms.