The f-block of the periodic table of the elements consists of those elements whose atoms or ions have valence electrons in f-orbitals. Actual electronic configurations may be slightly different from what is predicted by the Aufbau principle. The elements are also known as inner transition elements, although that term is normally taken to include lutetium and lawrencium as well, which are part of the d-block.[not verified in body]
f-block * Lanthanoids 57
La 58
Ce 59
Pr 60
Nd 61
Pm 62
Sm 63
Eu 64
Gd 65
Tb 66
Dy 67
Ho 68
Er 69
Tm 70
Yb
Atomic electron configuration 5d1 4f15d1 4f3 4f4 4f5 4f6 4f7 4f75d1 4f9 4f10 4f11 4f12 4f13 4f14
Electrons per shell 2, 8, 18,
18, 9,
2 2, 8, 18,
19, 9,
2 2, 8, 18,
21, 8,
2 2, 8, 18,
22, 8,
2 2, 8, 18,
23, 8,
2 2, 8, 18,
24, 8,
2 2, 8, 18,
25, 8,
2 2, 8, 18,
25, 9,
2 2, 8, 18,
27, 8,
2 2, 8, 18,
28, 8,
2 2, 8, 18,
29, 8,
2 2, 8, 18,
30, 8,
2 2, 8, 18,
31, 8,
2 2, 8, 18,
32, 8,
2
** Actinoids 89
Ac 90
Th 91
Pa 92
U 93
Np 94
Pu 95
Am 96
Cm 97
Bk 98
Cf 99
Es 100
Fm 101
Md 102
No
Atomic electron configuration 6d1 6d2 5f26d1or
5f16d2 5f36d1 5f46d1or
5f5 5f6 5f7 5f76d1 5f9
or 5f86d1 5f10 5f11 5f12 5f13 5f14
Electrons per shell 2, 8, 18, 32,
18, 9,
2 2, 8, 18, 32,
18, 10,
2 2, 8, 18, 32,
20, 9,
2 2, 8, 18, 32,
21, 9,
2 2, 8, 18, 32,
22, 9,
2 2, 8, 18, 32,
24, 8,
2 2, 8, 18, 32,
25, 8,
2 2, 8, 18, 32,
25, 9,
2 2, 8, 18, 32,
27, 8,
2 2, 8, 18, 32,
28, 8,
2 2, 8, 18, 32,
29, 8,
2 2, 8, 18, 32,
30, 8,
2 2, 8, 18, 32,
31, 8,
2 2, 8, 18, 32,
32, 8,
2
All elements in the lanthanide series form M3+ ions. In aqueous solution the early lanthanides are surrounded by nine water molecules while the later lanthanides have a coordination number of 8. Cerium also forms compounds with the +4 oxidation state; Ce4+ has the very stable electronic configuration of the noble gas xenon and is a strong oxidising agent. Eu2+ has the configuration [Xe]4f7 and is a strong reducing agent. The existence of Eu(II) is attributed to the stability of the half-filled f-shell.[1]
OMICS 