Femtosecond

A femtosecond is one billionth of one millionth, or one quadrillionth of a second. It can be written as 10^-15 second. Even shorter than this is an attosecond.

200 femtoseconds - the fastest chemical reactions
300 femtoseconds - how long it takes for the atoms of an iodine molecule to vibrate

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v t e Orders of magnitude (time), by powers of seconds
Negative powers	Planck time Quectosecond Rontosecond Yoctosecond Zeptosecond Attosecond Femtosecond Picosecond Nanosecond Microsecond Millisecond Centisecond Decisecond
Positive powers	Second Decasecond Hectosecond Kilosecond Megasecond Gigasecond Terasecond Petasecond Exasecond Zettasecond Yottasecond Ronnasecond Quettasecond