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Atomic Spectra Database

NIST Standard Reference Database 78

Version 5.11

Last Update to Data Content: December 2023 | Version History & Citation Information  |  Disclaimer | DOI:

Welcome to the NIST Atomic Spectra Database, NIST Standard Reference Database #78. The spectroscopic data may be selected and displayed according to wavelengths or energy levels by choosing one of the following options:


Spectral Lines

Spectral lines and associated energy levels displayed in wavelength order with all selected spectra intermixed or in multiplet order. Transition probabilities for the lines are also displayed where available.

Energy Levels

Energy levels of a particular atom or ion displayed in order of energy above the ground state.

Ground States and Ionization Energies

Ground states and ionization energies of atoms and atomic ions.


ASD Interface for Laser Induced Breakdown Spectroscopy (LIBS)

Additional information about the database may be obtained through the following links:

Atomic Spectroscopy Intro - Outlines basic atomic physics concepts, explains terminology and notation.

ASD Intro & Contents - Introduction to and contents of the Atomic Spectra Database.

Bibliography - Bibliography of data sources used for this database.

Help - On-line help in using the database.

This database provides access and search capability for NIST critically evaluated data on atomic energy levels, wavelengths, and transition probabilities that are reasonably up-to-date. The Atomic Spectroscopy Data Center has carried out these critical compilations. The Data Center is located in the Physical Measurement Laboratory at the National Institute of Standards and Technology (NIST).


Principal Developers (Currently Active):
Alexander Kramida, Yuri Ralchenko, and Joseph Reader

Data Compilers (Currently Active):
Alexander Kramida, Edward B. Saloman

Database Developers (Currently Active):
Alexander Kramida, Yuri Ralchenko, and Karen Olsen

Students contributing to data entry:
Eric Carpentier, Thomas Carpentier, Amy Zimmerman, Adrian Hamins-Puertolas, Marko Hamins-Puertolas, Anna Sharova, Genevieve Tan

Past Contributors:
Haris Kunari, Jean E. Sansonetti, Jeffrey R. Fuhr, Larissa I. Podobedova, Wolfgang L. Wiese, John J. Curry, Gerry R. Dalton, Robert Dragoset, Fun-Chen (Jesse) Jou, William C. Martin, Peter J. Mohr,  Arlene Musgrove, Craig J. Sansonetti, and Gloria Wiersma

©1979, 1980, 1981, 1982, 1983, 1985, 1988, 1990, 1991, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2005, 2006, 2007, 2008, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017 - copyright by the U.S. Department of Commerce on behalf of the United States. All rights reserved. NIST reserves the right to charge for these data in the future.

NIST Standard Reference Database 78
Customer Support
Online: March 1995 - Last update: December 2023

This database was funded [in part] by the Office of Fusion Energy Sciences of the U.S. Department of Energy, by the National Aeronautics and Space Administration, by NIST's Standard Reference Data Program (SRDP), and by NIST's SMA Program.


Created July 21, 2009, Updated December 5, 2023