If it is an element, it could be either chromium (Cr) or molybdenum (Mo). You need to know more to know which. The electronic configuration for Cr is:
[Ar]3d54s1
and for Mo it is
[Kr]4d55s1
So both elements have 5 d-electrons and 1 s-electron. I'm not sure if that what you mean however by "s1d5"...
Iron 2 is Fe 2+ and has electron configuration [Ar] s1d5 Iron 3 is Fe 3+ and has electron configuration [Ar] d5
The outer shell of the atoms in Group D will always be 1 or 2 s orbital electrons. Irregularities occur with Cr where it is s1d5, not s2d4 and in Group 11 metals it is s1d10 not s2d9 so that the d-subshell is complete at Group 11.