Atomic radii of the elements (data page)

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The atomic radius of a chemical element is the distance from the center of the nucleus to the outermost shell of an electron. Since the boundary is not a well-defined physical entity, there are various non-equivalent definitions of atomic radius. Depending on the definition, the term may apply only to isolated atoms, or also to atoms in condensed matter, covalently bound in molecules, or in ionized and excited states; and its value may be obtained through experimental measurements, or computed from theoretical models. Under some definitions, the value of the radius may depend on the atom's state and context. [1]

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Atomic radii vary in a predictable and explicable manner across the periodic table. For instance, the radii generally decrease rightward along each period (row) of the table, from the alkali metals to the noble gases; and increase down each group (column). The radius increases sharply between the noble gas at the end of each period and the alkali metal at the beginning of the next period. These trends of the atomic radii (and of various other chemical and physical properties of the elements) can be explained by the electron shell theory of the atom; they provided important evidence for the development and confirmation of quantum theory.

Atomic radius

Note: All measurements given are in picometers (pm). For more recent data on covalent radii see Covalent radius. Just as atomic units are given in terms of the atomic mass unit (approximately the proton mass), the physically appropriate unit of length here is the Bohr radius, which is the radius of a hydrogen atom. The Bohr radius is consequently known as the "atomic unit of length". It is often denoted by a0 and is approximately 53 pm. Hence, the values of atomic radii given here in picometers can be converted to atomic units by dividing by 53, to the level of accuracy of the data given in this table.

Atomic radii up to zinc (30) Atomic radii up to zinc.png
Atomic radii up to zinc (30)
atomic numbersymbolname empirical † Calculated van der Waals Covalent (single bond)Covalent (triple bond)Metallic
1H hydrogen 25 [2] 53[ citation needed ]120 [3] or 110 [4] 32
2He helium 120[ citation needed ]31 [5] 140 [3] [4] 46
3Li lithium 145 [2] 167 [5] 182 [3] or 181 [4] 133152
4Be beryllium 105 [2] 112 [5] 153 [4] 10285 [6] 112
5B boron 85 [2] 87 [5] 192 [4] 8573 [6]
6C carbon 70 [2] 67 [5] 170 [3] [4] 7560 [6]
7N nitrogen 65 [2] 56 [5] 155 [3] [4] 7154 [6]
8O oxygen 60 [2] 48 [5] 152 [3] [4] 6353 [6]
9F fluorine 50 [2] 42 [5] 147 [3] [4] 6453 [6]
10Ne neon 160[ citation needed ] [7] 38 [5] 154 [3] [4] 67
11Na sodium 180 [2] 190 [5] 227 [3] [4] 155186
12Mg magnesium 150 [2] 145 [5] 173 [3] [4] 139127 [6] 160
13Al aluminium 125 [2] 118 [5] 184 [4] 126111 [6] 143
14Si silicon 110 [2] 111 [5] 210 [3] [4] 116102 [6]
15P phosphorus 100 [2] 98 [5] 180 [3] [4] 11194 [6]
16S sulfur 100 [2] 88 [5] 180 [3] [4] 10395 [6]
17Cl chlorine 100 [2] 79 [5] 175 [3] [4] 9993 [6]
18Ar argon 71[ citation needed ]71 [5] 188 [3] [4] 9696 [6]
19K potassium 220 [2] 243 [5] 275 [3] [4] 196227
20Ca calcium 180 [2] 194 [5] 231 [4] 171133 [6] 197
21Sc scandium 160 [2] 184 [5] 211[ citation needed ]148114 [6] 162 b
22Ti titanium 140 [2] 176 [5] 136108 [6] 147
23V vanadium 135 [2] 171 [5] 134106 [6] 134 b
24Cr chromium 140 [2] 166 [5] 122103 [6] 128 b
25Mn manganese 140 [2] 161 [5] 119103 [6] 127 b
26Fe iron 140 [2] 156 [5] 116102 [6] 126 b
27Co cobalt 135 [2] 152 [5] 11196 [6] 125 b
28Ni nickel 135 [2] 149 [5] 163 [3] 110101 [6] 124 b
29Cu copper 135 [2] 145 [5] 140 [3] 112120 [6] 128 b
30Zn zinc 135 [2] 142 [5] 139 [3] 118134 b
31Ga gallium 130 [2] 136 [5] 187 [3] [4] 124121 [6] 135 c
32Ge germanium 125 [2] 125 [5] 211 [4] 121114 [6]
33As arsenic 115 [2] 114 [5] 185 [3] [4] 121106 [6]
34Se selenium 115 [2] 103 [5] 190 [3] [4] 116107 [6]
35Br bromine 115 [2] 94 [5] 185 [3] or 183 [4] 114110 [6]
36Kr krypton 88 [5] 202 [3] [4] 117108 [6]
37Rb rubidium 235 [2] 265 [5] 303 [4] 210248
38Sr strontium 200 [2] 219 [5] 249 [4] 185139 [6] 215
39Y yttrium 180 [2] 212 [5] 163124 [6] 180 b
40Zr zirconium 155 [2] 206 [5] 154121 [6] 160
41Nb niobium 145 [2] 198 [5] 147116 [6] 146 b
42Mo molybdenum 145 [2] 190 [5] 138113 [6] 139 b
43Tc technetium 135 [2] 183 [5] 128110 [6] 136 b
44Ru ruthenium 130 [2] 178 [5] 125103 [6] 134 b
45Rh rhodium 135 [2] 173 [5] 125106 [6] 134 b
46Pd palladium 140 [2] 169 [5] 163 [3] 120112 [6] 137 b
47Ag silver 160 [2] 165 [5] 172 [3] 128137 [6] 144 b
48Cd cadmium 155 [2] 161 [5] 158 [3] 136151 b
49In indium 155 [2] 156 [5] 193 [3] [4] 142146 [6] 167
50Sn tin 145 [2] 145 [5] 217 [3] [4] 140132 [6]
51Sb antimony 145 [2] 133 [5] 206 [4] 140127 [6]
52Te tellurium 140 [2] 123 [5] 206 [3] [4] 136121 [6]
53I iodine 140 [2] 115 [5] 198 [3] [4] 133125 [6]
54Xe xenon 108 [5] 216 [3] [4] 131122 [6]
55Cs caesium 260 [2] 298 [5] 343 [4] 232265
56Ba barium 215 [2] 253 [5] 268 [4] 196149 [6] 222
57La lanthanum 195 [2] 226[ citation needed ]180139 [6] 187 b
58Ce cerium 185 [2] 210[ citation needed ]163131 [6] 181.8 c
59Pr praseodymium 185 [2] 247 [5] 176128 [6] 182.4 c
60Nd neodymium 185 [2] 206 [5] 174181.4 c
61Pm promethium 185 [2] 205 [5] 173183.4 c
62Sm samarium 185 [2] 238 [5] 172180.4 c
63Eu europium 185 [2] 231 [5] 168180.4 c
64Gd gadolinium 180 [2] 233 [5] 169132 [6] 180.4 c
65Tb terbium 175 [2] 225 [5] 168177.3 c
66Dy dysprosium 175 [2] 228 [5] 167178.1 c
67Ho holmium 175 [2] 226 [5] 166176.2 c
68Er erbium 175 [2] 226 [5] 165176.1 c
69Tm thulium 175 [2] 222 [5] 164175.9 c
70Yb ytterbium 175 [2] 222 [5] 170176 c
71Lu lutetium 175 [2] 217 [5] 162131 [6] 173.8 c
72Hf hafnium 155 [2] 208 [5] 152122 [6] 159
73Ta tantalum 145 [2] 200 [5] 146119 [6] 146 b
74W tungsten 135 [2] 193 [5] 137115 [6] 139 b
75Re rhenium 135 [2] 188 [5] 131110 [6] 137 b
76Os osmium 130 [2] 185 [5] 129109 [6] 135 b
77Ir iridium 135 [2] 180 [5] 122107 [6] 135.5 b
78Pt platinum 135 [2] 177 [5] 175 [3] 123110 [6] 138.5 b
79Au gold 135 [2] 174 [5] 166 [3] 124123 [6] 144 b
80Hg mercury 150 [2] 171 [5] 155 [3] 133151 b
81Tl thallium 190 [2] 156 [5] 196 [3] [4] 144150 [6] 170
82Pb lead 180[ citation needed ]154 [5] 202 [3] [4] 144137 [6]
83Bi bismuth 160 [2] 143 [5] 207 [4] 151135 [6]
84Po polonium 190 [2] 135 [5] 197 [4] 145129 [6]
85At astatine 127 [5] 202 [4] 147138 [6]
86Rn radon 120 [5] 220 [4] 142133 [6]
87Fr francium 348 [4]
88Ra radium 215 [2] 283 [4] 201159 [6]
89Ac actinium 195 [2] 186140 [6]
90Th thorium 180 [2] 175136 [6] 179 b
91Pa protactinium 180 [2] 169129 [6] 163 d
92U uranium 175 [2] 186 [3] 170118 [6] 156 e
93Np neptunium 175 [2] 171116 [6] 155 e
94Pu plutonium 175 [2] 172159 e
95Am americium 175 [2] 166173 b
96Cm curium 176[ citation needed ]166174 b
97Bk berkelium 170 b
98Cf californium 186±2 b
99Es einsteinium 186±2 b
100Fm fermium
101Md mendelevium
102No nobelium
103Lr lawrencium
104Rf rutherfordium 131 [6]
105Db dubnium 126 [6]
106Sg seaborgium 121 [6]
107Bh bohrium 119 [6]
108Hs hassium 118 [6]
109Mt meitnerium 113 [6]
110Ds darmstadtium 112 [6]
111Rg roentgenium 118 [6]
112Cn copernicium 130 [6]
113Nh nihonium
114Fl flerovium
115Mc moscovium
116Lv livermorium
117Ts tennessine
118Og oganesson

See also

Notes

Related Research Articles

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References

  1. ↑ Cotton, F. A.; Wilkinson, G. (1988). Advanced Inorganic Chemistry (5th ed.). Wiley. p. 1385. ISBN   978-0-471-84997-1.
  2. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 J.C. Slater (1964). "Atomic Radii in Crystals". The Journal of Chemical Physics. 41 (10): 3199–3204. Bibcode:1964JChPh..41.3199S. doi:10.1063/1.1725697.
  3. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 A. Bondi (1964). "van der Waals Volumes and Radii". The Journal of Physical Chemistry. 68 (3): 441–451. doi:10.1021/j100785a001.
  4. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 Mantina, Manjeera; Chamberlin, Adam C.; Valero, Rosendo; Cramer, Christopher J.; Truhlar, Donald G. (2009-04-21). "Consistent van der Waals Radii for the Whole Main Group". The Journal of Physical Chemistry A. 113 (19). American Chemical Society (ACS): 5806–5812. Bibcode:2009JPCA..113.5806M. doi:10.1021/jp8111556. ISSN   1089-5639. PMC   3658832 . PMID   19382751.
  5. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 E. Clementi; D.L.Raimondi; W.P. Reinhardt (1967). "Atomic Screening Constants from SCF Functions. II. Atoms with 37 to 86 Electrons". The Journal of Chemical Physics. 47 (4): 1300–1307. Bibcode:1967JChPh..47.1300C. doi:10.1063/1.1712084.
  6. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 S. Riedel; P.Pyykkö, M. Patzschke; Patzschke, M (2005). "Triple-Bond Covalent Radii". Chem. Eur. J. 11 (12): 3511–3520. doi:10.1002/chem.200401299. PMID   15832398.
  7. ↑ Neon has van der Waal's radii thus its radii is the highest in its period
  8. ↑ "Empirical Definition & Meaning - Merriam-Webster".

Data is as quoted at http://www.webelements.com/ from these sources:

Covalent radii (single bond)

Metallic radius

Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN   978-0-08-037941-8.

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