fine structure

American  

[fahyn] / faɪn /

noun

Physics.

1. a group of lines that are observed in the spectra of certain elements, as hydrogen, and that are caused by various couplings of the azimuthal quantum number and the angular momentum quantum number.

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fine structure British  

noun

1. the splitting of a spectral line into two or more closely spaced components as a result of interaction between the spin and orbital angular momenta of the atomic electrons Compare hyperfine structure

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Etymology

Origin of fine structure

First recorded in 1915–20

Example Sentences

Then, more charge-bearing particles invade the transistor's flexible structure, causing it to swell slightly and bringing current up to operational levels.

From Science Daily • Apr. 30, 2024

Seeing “Shockwave Delay” twice revealed that beneath its haphazard surface‌‌ is a solid if flexible structure, complex in its malleability.

From New York Times • Jun. 6, 2023

In the wake of the storm, this decentralized, highly flexible structure proved to be a strength.

From Time • Nov. 13, 2012

Many believe that the American economy has some inherent advantages over its major competitors — a more flexible structure, stronger entrepreneurial traditions and a more demographically vibrant society.

From Washington Post

Some animals of gelatinous, and therefore flexible structure, perform digestion by folding their bodies over the food, and pressing the nutritious matter out of it: they extemporize a stomach for the occasion.

From The Continental Monthly, Vol. 3, No. 1 January 1863 Devoted To Literature And National Policy by Various