PHz

petahertz

Frequencyexact by definition

The petahertz is 10¹⁵ hertz. Visible light lives here: 550 nm green light oscillates at about 545 THz, or 0.545 PHz, and ultraviolet runs above one petahertz. It is also the natural frequency unit for attosecond science, since a petahertz cycle lasts one femtosecond.

1 PHz 1.0000000e+15 Hz