A table or chart of nuclides is a two-dimensional graph of isotopes of the elements, in which one axis represents the number of neutrons (symbol N) and the other represents the number of protons (atomic number, symbol Z) in the atomic nucleus. Each point plotted on the graph thus represents a nuclide of a known or hypothetical chemical element. This system of ordering nuclides can offer a greater insight into the characteristics of isotopes than the better-known periodic table, which shows only elements and not their isotopes. The chart of the nuclides is also known as the Segrè chart, after the Italian physicist Emilio Segrè.^[1]

Description and utility

A chart or table of nuclides maps the nuclear, or radioactive, behavior of nuclides, as it distinguishes the isotopes of an element. It contrasts with a periodic table, which only maps their chemical behavior, since isotopes (nuclides which are variants of the same element) do not differ chemically to any significant degree, with the exception of hydrogen. Nuclide charts organize nuclides along the X axis by their numbers of neutrons and along the Y axis by their numbers of protons, out to the limits of the neutron and proton drip lines. This representation was first published by Kurt Guggenheimer in 1934^[2] and expanded by Giorgio Fea in 1935,^[3] Emilio Segrè in 1945 or Glenn Seaborg. In 1958, Walter Seelmann-Eggebert and Gerda Pfennig published the first edition of the Karlsruhe Nuclide Chart. Its 7th edition was made available in 2006. Today, there are several nuclide charts, four of which have a wide distribution: the Karlsruhe Nuclide Chart, the Strasbourg Universal Nuclide Chart, the Chart of the Nuclides from the Japan Atomic Energy Agency (JAEA), and the Nuclide Chart from Knolls Atomic Power Laboratory in the United States.^[4] It has become a basic tool of the nuclear community.

Trends in the chart of nuclides

The trends in this section refer to the following chart, which shows Z increasing to the right and N increasing downward, a 90° clockwise rotation of the above landscape-orientation charts.

	5	6H	7He	8Li	9Be	10B	11C	12N	13O	14F	15Ne	Na	Mg
	6	7H	8He	9Li	10Be	11B	12C	13N	14O	15F	16Ne	17Na	18Mg	13	14
		7	9He	10Li	11Be	12B	13C	14N	15O	16F	17Ne	18Na	19Mg	Al	Si
		8	10He	11Li	12Be	13B	14C	15N	16O	17F	18Ne	19Na	20Mg		22Si
			9	12Li	13Be	14B	15C	16N	17O	18F	19Ne	20Na	21Mg	22Al	23Si

• Isotopes are nuclides with the same number of protons but differing numbers of neutrons; that is, they have the same atomic number and are therefore the same chemical element. Isotopes neighbor each other vertically. Examples include carbon-12, carbon-13, and carbon-14 in the table above.
• Isotones are nuclides with the same number of neutrons but differing numbers of protons. Isotones neighbor each other horizontally. Examples include carbon-14, nitrogen-15, and oxygen-16 in the table above.
• Isobars are nuclides with the same number of nucleons (i.e. mass number) but different numbers of protons and neutrons. Isobars neighbor each other diagonally from lower-left to upper-right. Examples include carbon-14, nitrogen-14, and oxygen-14 in the table above.
• Isodiaphers are nuclides with the same difference between their numbers of neutrons and protons (N − Z). Like isobars, they follow diagonal lines, but at right angles to the isobar lines (from upper-left to lower-right). Examples include boron-10, carbon-12, and nitrogen-14 (as N − Z = 0 for each pair), or boron-12, carbon-14, and nitrogen-16 (as N − Z = 2 for each pair).
• Beyond the neutron drip line along the lower left, nuclides decay by neutron emission.
• Beyond the proton drip line along the upper right, nuclides decay by proton emission. Drip lines have only been established for some elements.
• The island of stability is a hypothetical region in the top right cluster of nuclides that contains isotopes far more stable than other transuranic elements.
• There are no stable nuclides having an equal number of protons and neutrons in their nuclei with atomic number greater than 20 (i.e. calcium) as can be readily observed from the chart. Nuclei of greater atomic number require an excess of neutrons for stability.
• The only stable nuclides having an odd number of protons and an odd number of neutrons are hydrogen-2, lithium-6, boron-10, nitrogen-14 and (observationally) tantalum-180m. This is because the mass–energy of such atoms is usually higher than that of their neighbors on the same isobaric chain, so most of them are unstable to beta decay.
• There are no stable nuclides with mass numbers 5 or 8. There are stable nuclides with all other mass numbers up to 208 with the exceptions of 147 and 151, which are represented by the very long-lived samarium-147 and europium-151. (Bismuth-209 was found to be radioactive in 2003, but with a half-life of 1.9×10¹⁹ years.)
• With the exception of the pair tellurium-123 and antimony-123, odd mass numbers are never represented by more than one stable nuclide. This is because the mass–energy is a convex function of atomic number, so all nuclides on an odd isobaric chain except one have a lower-energy neighbor to which they can decay by beta decay. See Mattauch isobar rule. (¹²³Te is expected to decay to ¹²³Sb, but the half-life appears to be so long that the decay has never been observed.)
• There are no stable nuclides having atomic number greater than Z = 82 (lead),^[5] although bismuth (Z = 83) is stable for all practical human purposes and thorium (Z = 90) and uranium (Z = 92) are sufficiently long-lived to occur on Earth in large quantities. Elements with atomic numbers from 1 to 82 all have stable isotopes, with the exceptions of technetium (Z = 43) and promethium (Z = 61).

Tables

Half-lives (example: Gd)

145Gd	< 1 day
149Gd	1–10 days
146Gd	10–100 days
153Gd	100 days–10 a
148Gd	10–10,000 a
150Gd	10 ka–700 Ma
152Gd	> 700 Ma
158Gd	Stable
94Nb	Border: Isomer is < 1 day
198Au	Border: Isomer is 1–10 days
91Nb	Border: Isomer is 10–100 days
102Rh	Border: Isomer is 100 days – 10 years
93Nb	Border: Isomer is 10–10,000 years
204Pb	Border: Isomer is 10k–103M years
180Ta	Border: Isomer is Stable

For convenience, three different views of the data are available on Wikipedia: two sets of "segmented tables", and a single "unitized table (all elements)". The unitized table allows easy visualizion of proton/neutron-count trends but requires simultaneous horizontal and vertical scrolling. The segmented tables permit easier examination of a particular chemical element with much less scrolling. Links are provided to quickly jump between the different sections.

Segmented tables

• Table of nuclides (segmented, narrow)
• Table of nuclides (segmented, wide)

Full table

The nuclide table below shows nuclides (often loosely called "isotopes", but this term properly refers to nuclides with the same atomic number, see above), including all with half-life of at least one day.^[6] They are arranged with increasing atomic numbers from left to right and increasing neutron numbers from top to bottom.

Cell color denotes the half-life of each nuclide; if a border is present, its color indicates the half-life of the most stable nuclear isomer. In graphical browsers, each nuclide also has a tool tip indicating its half-life. Each color represents a certain range of length of half-life, and the color of the border indicates the half-life of its nuclear isomer state. Some nuclides have multiple nuclear isomers, and this table notes the one with the longest half-life. Dotted borders mean that a nuclide has a nuclear isomer with a half-life in the same range as the ground state nuclide. The dashed lines between several nuclides of the first few elements are the experimentally determined proton and neutron drip lines.

Zdroj:https://en.wikipedia.org?pojem=Table_of_nuclides
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Z →	0	1	2	3
n ↓	n	H	He	Li	4	5
0		1H			Be	B	6	7
1	1n	2H	3He	4Li			C	N	8
2		3H	4He	5Li	6Be	7B	8C	9N	O	9
3		4H	5He	6Li	7Be	8B	9C	10N	11O	F	10
4		5H	6He	7Li	8Be	9B	10C	11N	12O	13F	Ne	11	12
	5	6H	7He	8Li	9Be	10B	11C	12N	13O	14F	15Ne	Na	Mg
	6	7H	8He	9Li	10Be	11B	12C	13N	14O	15F	16Ne	17Na	18Mg	13	14
		7	9He	10Li	11Be	12B	13C	14N	15O	16F	17Ne	18Na	19Mg	Al	Si	15
		8	10He	11Li	12Be	13B	14C	15N	16O	17F	18Ne	19Na	20Mg		22Si	P	16
			9	12Li	13Be	14B	15C	16N	17O	18F	19Ne	20Na	21Mg	22Al	23Si		S	17	18
			10	13Li	14Be	15B	16C	17N	18O	19F	20Ne	21Na	22Mg	23Al	24Si			Cl	Ar	19
				11	15Be	16B	17C	18N	19O	20F	21Ne	22Na	23Mg	24Al	25Si	26P	27S	28Cl	29Ar	K	20
				12	16Be	17B	18C	19N	20O	21F	22Ne	23Na	24Mg	25Al	26Si	27P	28S	29Cl	30Ar	31K	Ca	21
					13	18B	19C	20N	21O	22F	23Ne	24Na	25Mg	26Al	27Si	28P	29S	30Cl	31Ar			Sc	22
					14	19B	20C	21N	22O	23F	24Ne	25Na	26Mg	27Al	28Si	29P	30S	31Cl	32Ar	33K			Ti	23
					15	20B		22N	23O	24F	25Ne	26Na	27Mg	28Al	29Si