metastable ion


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metastable ion

[¦med·ə′stā·bəl ′ī‚än]
(analytical chemistry)
In mass spectroscopy, an ion formed by a secondary dissociation process in the analyzer tube (formed after the parent or initial ion has passed through the accelerating field).
References in periodicals archive ?
"The DSA's use of nitrogen gas provides true molecular ions instead of metastable ions, allowing for easier data interpretation," says Crowe.
The ions that have just sufficient energy to fragment some time after leaving the ion source, but before arriving at the detector are called "metastable ions".
An energy slit in the spectrometer also allows it to operate in a bandpass mode rather than a low-pass mode - low energy metastable ions are rejected, leading to lower background counts and better detection limits.