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I don't understand why it varies between Group 10 metals (as with Palladium, Platinum and Darmstadtium) and Copper (Group 11). If each of Palladium, Platinum and Darmstadtium entirely filled the 3d/4d/5d shells then it would make more conceptual sense, but both Platinum and Darmstadtium still have +1/2 spin in the final 4d/5d shell.


marked as duplicate by Philipp, Michael DM Dryden, Freddy, Wildcat, LievenB Sep 27 '14 at 7:58

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  • $\begingroup$ a similar question is here chemistry.stackexchange.com/questions/11069/… $\endgroup$ – agha rehan abbas Aug 18 '14 at 18:19
  • $\begingroup$ That kind of question comes up regularly but unfortunately there is no easy way to answer it. Have a look at this and this question. $\endgroup$ – Philipp Aug 18 '14 at 18:20
  • $\begingroup$ @Philipp -- that's fine, I'm okay with weird explanations. I'm glad I'm not just missing a fundamental exception to the Aufbau principle. Or is there a rule? $\endgroup$ – MattKneale Aug 18 '14 at 18:24
  • $\begingroup$ Well, there is no rule I know of. $\endgroup$ – Philipp Aug 18 '14 at 19:00