The purpose of this paper is to make a brief survey of the knowledge of iron group elements as concerns energy levels and transition arrays in neutral and singly ionized atoms and to give rough predictions of missing levels and lines. The amount of data that have been published for these elements after the edition of the Multiplet Tables are considerable. For detailed information about sources of new data and compilations the reader is referred to the Report from Commission 14 in the Transactions of IAU. In this paper we will focus on still missing energy levels and associated missing transitions, which have to be considered in the construction of synthetic spectra.
The structure of the iron group elements is complex not only because of the filling of the 3d shell but also because of the competition in binding energy between the 3d- and the 4s electron. For a given number of valence electrons, k, we have to consider three different low configurations in the complex (3d + 4s)k having about the same energy in neutral and singly ionized atoms. In neutral atoms the 3dk−2 4s2 configuration generally occupies the ground state, while the 3dk configuration appears at rather high excitation energy. In the singly ionized atoms all three configurations have about the same energy, giving the most pronounced complexity.
To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Find out more about the Kindle Personal Document Service.
To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Dropbox.
To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Google Drive.