Shell: d-block

 .                                                  ..
 .. ..                               .  .  .  .  .  ..
 .. ..                               .. .. .  .  .. ..
 .  .. Sc Ti V  Cr Mn Fe Co Ni Cu Zn .. .. .. .. .. ..
 .. .. Y  Zr Nb Mo Tc Ru Rh Pd Ag Cd .. .. .. .. .  ..
 .. .. .. Hf Ta W  Re Os Ir Pt Au Hg .. .. .. .. .. ..
 .. .. .. Rf Db Sg Bh Hs Mt Ds Rg Cn .. .. .. .. .. ..
                                                      
       .. .. .. .. .. .. .. .. .. .. .. .. .. ..      
       .. .. .  .. .. .. .. .. .. .. .. .. .. ..      

The d-block consists of elements in Groups 3 to 12. The valence 
electrons of these elements are in the d-shell. This shell holds at 
most 10 electrons, and has an azimuthal quantum number of 2. The "d" 
stands for "diffuse".

 21 Sc Scandium
 22 Ti Titanium
 23 V  Vanadium
 24 Cr Chromium
 25 Mn Manganese
 26 Fe Iron
 27 Co Cobalt
 28 Ni Nickel
 29 Cu Copper
 30 Zn Zinc
 39 Y  Yttrium
 40 Zr Zirconium
 41 Nb Niobium
 42 Mo Molybdenum
 43 Tc Technetium
 44 Ru Ruthenium
 45 Rh Rhodium
 46 Pd Palladium
 47 Ag Silver
 48 Cd Cadmium
 72 Hf Hafnium
 73 Ta Tantalum
 74 W  Tungsten
 75 Re Rhenium
 76 Os Osmium
 77 Ir Iridium
 78 Pt Platinum
 79 Au Gold
 80 Hg Mercury
104 Rf Rutherfordium
105 Db Dubnium
106 Sg Seaborgium
107 Bh Bohrium
108 Hs Hassium
109 Mt Meitnerium
110 Ds Darmstadtium
111 Rg Roentgenium
112 Cn Copernicium