d-block

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For other uses, see D block (disambiguation).
d-block in the periodic table
3 4 5 6 7 8 9 10 11 12
Group →
↓ Period
4 21
Sc
22
Ti
23
V
24
Cr
25
Mn
26
Fe
27
Co
28
Ni
29
Cu
30
Zn
5 39
Y
40
Zr
41
Nb
42
Mo
43
Tc
44
Ru
45
Rh
46
Pd
47
Ag
48
Cd
6 71
Lu
72
Hf
73
Ta
74
W
75
Re
76
Os
77
Ir
78
Pt
79
Au
80
Hg
7 103
Lr
104
Rf
105
Db
106
Sg
107
Bh
108
Hs
109
Mt
110
Ds
111
Rg
112
Cn

The d-block is the block or portion of the periodic table that contains the element groups 3–12.[1][2] These groups correspond to the filling of the atomic d-orbital subshell of the second outermost shell (inside an outermost shell only containing 1 or 2 s-orbital electrons) with electron configurations ranging from s2d1 (Group 3) to s2d10 (Group 12). There are some irregularities in the sequence; for example Cr is s1d5 (not s2d4) and the Group 11 metals are s1d10 (not s2d9), so that the d-subshell is actually complete at Group 11.

The d-block elements are often also known as transition metals or transition elements. However, the exact limits of the transition metal region are usually not considered to be identical to the d-block. Although some authors do identify the entire d-block (groups 3 to 12) as transition metals,[1] most define transition metals as elements with partly filled d subshells either in the neutral atom or in ions in common oxidation states.[2][3] This definition corresponds to including only Groups 3–11 as transition metals. Group 12 metals lack the characteristic chemical and physical properties associated with incomplete d subshells and are considered post-transition metals. Jensen has reviewed the historical usage of the terms transition element (or metal) and d-block.[4] IUPAC allows both definitions.

In the s-block and p-block of the periodic table, similar properties across the periods are generally not observed: the most important similarities tend to be vertical, down groups. However the d-block is notable in that horizontal similarities across the periods do become important.

Although lutetium and lawrencium are in the d-block, they are not considered transition metals but a lanthanide and an actinide, respectively, according to IUPAC.[5] Group 12 elements are also in the d-block but are sometimes considered post-transition metals as their d-subshell is completely filled.[5]

Electron shells filled in violation of Madelung's rule[6][7] (red) [note 1]
Period 4 after [Ar]   Period 5 after [Kr]   Period 6 after [Xe]   Period 7 after [Rn]   Period 8 after [Uuo]
Scandium 21 4s2 3d1   Yttrium 39 5s2 4d1   Lutetium 71 6s2 4f14 5d1   Lawrencium 103 7s2 4f14 7p1?   Unpentpentium 155 5g18 6f13 7d2 8s2 8p2??
Titanium 22 4s2 3d2   Zirconium 40 5s2 4d2   Hafnium 72 6s2 4f14 5d2   Rutherfordium 104 7s2 4f14 6d2?   Unpenthexium 156 5g18 6f14 7d2 8s2 8p2??
Vanadium 23 4s2 3d3   Niobium 41 5s1 4d4   Tantalum 73 6s2 4f14 5d3   Dubnium 105 7s2 4f14 6d3??   Unpentseptium 157 5g18 6f14 7d3 8s2 8p2??
Chromium 24 4s1 3d5   Molybdenum 42 5s1 4d5   Tungsten 74 6s2 4f14 5d4   Seaborgium 106 7s2 4f14 6d4??   Unpentoctium 158 5g18 6f14 7d4 8s2 8p2??
Manganese 25 4s2 3d5   Technetium 43 5s2 4d5   Rhenium 75 6s2 4f14 5d5   Bohrium 107 7s2 4f14 6d5??   Unpentennium 159 5g18 6f14 7d4 8s2 8p2 9s1??
Iron 26 4s2 3d6   Ruthenium 44 5s1 4d7   Osmium 76 6s2 4f14 5d6   Hassium 108 7s2 4f14 6d6??   Unhexnilium 160 5g18 6f14 7d5 8s2 8p2 9s1??
Cobalt 27 4s2 3d7   Rhodium 45 5s1 4d8   Iridium 77 6s2 4f14 5d7   Meitnerium 109 7s2 4f14 6d7??   Unhexunium 161 5g18 6f14 7d6 8s2 8p2 9s1??
Nickel *[8] 28 4s2 3d8 or
4s1 3d9
Palladium 46 4d10   Platinum 78 6s1 4f14 5d9   Darmstadtium 110 7s2 4f14 6d8??   Unhexbium 162 5g18 6f14 7d8 8s2 8p2??
Copper 29 4s1 3d10   Silver 47 5s14d10   Gold 79 6s1 4f14 5d10   Roentgenium 111 7s2 4f14 6d9??   Unhextrium 163 5g18 6f14 7d9 8s2 8p2??
Zinc 30 4s2 3d10   Cadmium 48 5s2 4d10   Mercury 80 6s2 4f14 5d10   Copernicium 112 7s2 4f14 6d10??   Unhexquadium 164 5g18 6f14 7d10 8s2 8p2??

See also[edit]

Notes[edit]

  1. ^ A single question mark after the electron configuration indicates that it is tentative and unconfirmed, though it has been experimentally determined; a double question mark indicates that it is a prediction and has not yet been experimentally confirmed.

References[edit]

  1. ^ a b R.H. Petrucci, W.S. Harwood and F.G. Herring “General Chemistry” (8th ed, Prentice-Hall 2002), p.341-2
  2. ^ a b C.E. Housecroft and A.G. Sharpe “Inorganic Chemistry” (2nd ed, Pearson Prentice-Hall 2005), p..20-21
  3. ^ F.A. Cotton and G. Wilkinson “Advanced Inorganic Chemistry” (5th ed, John Wiley 1988) p.625
  4. ^ Jensen, William B. (2003). "The Place of Zinc, Cadmium, and Mercury in the Periodic Table". Journal of Chemical Education 80 (8): 952–961. Bibcode:2003JChEd..80..952J. doi:10.1021/ed080p952. 
  5. ^ a b IUPAC Provisional Recommendations for the Nomenclature of Inorganic Chemistry (2004) (online draft of an updated version of the "Red Book" IR 3–6)
  6. ^ G.L. Miessler and D.A. Tarr, "Inorganic Chemistry" (2nd ed., Prentice-Hall 1999) p.38
  7. ^ See references in the article: electron configurations of the elements (data page)
  8. ^ Scerri, Eric R. (2007). The periodic table: its story and its significance. Oxford University Press. pp. 239–240. ISBN 0-19-530573-6.