The Spectrum of Singly Ionized Atomic Iodine (I ii)
Summary
This study details the I ii spectrum, identifying thousands of spectral lines and significantly expanding known energy levels. New findings include magnetic dipole transitions and the principal ionization energy for I ii.
Area of Science:
- Atomic Physics
- Spectroscopy
- Quantum Mechanics
Background:
- Previous analysis of the I ii spectrum was limited, necessitating a comprehensive revision.
- Understanding atomic energy levels is crucial for various physics and chemistry applications.
Purpose of the Study:
- To re-analyze and extend the known energy levels and spectral lines of the I ii spectrum.
- To investigate specific spectral features, including magnetic dipole transitions and hyperfine structure.
- To determine the principal ionization energy of I ii.
Main Methods:
- Excitation of the I ii spectrum in electrodeless lamps.
- Photographic recording of spectral lines across a wide wavelength range (655 A to 11084 A).
- Analysis of spectral lines to identify and classify energy levels, including g-factors and intermediate coupling theory.
Main Results:
- Cataloged nearly 2,400 spectral lines with wavelengths and intensities.
- Increased known even levels from 43 to 124 and odd levels from 55 to 190.
- Observed magnetic dipole transitions and confirmed hyperfine structure; derived ionization energy of 154304 ±1 cm⁻¹.
Conclusions:
- The revised analysis significantly enhances the understanding of the I ii atomic structure.
- New data provides a more accurate foundation for theoretical atomic physics calculations.
- The study successfully identified new spectral series and confirmed theoretical predictions.
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