# On the periodic table: Why are groups of elements organized by 'letter' [duplicate]

Why are the groups of elements on the periodic table organized into areas represented by the letters s,p,d,f,g, and h? What does this mean?

• Letters g and h confuse me a bit. Could you please provide an example of elements that belong to these groups? Jul 10 '17 at 4:13
• The s, p, d, and f stand for "sharp," "principal," "diffuse," and "fundamental," respectively. After f comes g,h,i....and so on... Jul 10 '17 at 4:26
• These areas are called blocks and the letters correspond to the last orbital to be filled by electrons for that block, and they thus exhibit trends or commonalities in chemical properties. Wikipedia gives a pretty good discussion here. Jul 10 '17 at 4:30
• This all is just great, spectroscopic notations and stuff, but from the question it looks like OP encountered a PTE with g and h blocks, which I'd really like to look at. Jul 10 '17 at 4:52
• Possible duplicate of Periodic table and p block elements, and also of What is SPDF configuration?
– Nij
Jul 10 '17 at 4:57