Nihonium

The first element discovered in Asia, named after Japan.

At a glance

Symbol: Nh
Atomic number: 113
Mass number of its longest-lived isotope: [286]
Group: 13
Period: 7
Family: superheavy element
Electron configuration: [Rn] 5f¹⁴ 6d¹⁰ 7s² 7p¹ (predicted)
Electronegativity: not measured

On the table

Period 7, group 13. The other superheavy elements are tinted, and every cell opens its own article.

Electrons and bonding

Nihonium has 113 electrons, one for every proton, so the atom carries no charge. Below are the same 113 electrons written two ways.

Simple form: electrons per shell

shell 12shell 28shell 318shell 432shell 532shell 618shell 73

Counting outward from the nucleus: 2, 8, 18, 32, 32, 18, 3. The outer shell is picked out.

Orbital form: electrons per subshell

1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 5f¹⁴ 6s² 6p⁶ 6d¹⁰ 7s² 7p¹

Short form: [Rn] 5f¹⁴ 6d¹⁰ 7s² 7p¹, where [Rn] stands for the 86 electrons radon already has.

That list runs by shell. In the order the subshells fill it reads [Rn] 7s² 5f¹⁴ 6d¹⁰ 7p¹, because a subshell fills by its energy, not by its shell number.

5f¹⁴↑↓↑↓↑↓↑↓↑↓↑↓↑↓

6d¹⁰↑↓↑↓↑↓↑↓↑↓

7s²↑↓

7p¹↑

The boxes hold the electrons beyond [Rn]. Each box is one orbital and takes two electrons at most, spinning opposite ways. They spread out singly before they pair up.

How to read the two

The simple form counts electrons shell by shell. The orbital form says which subshell each one sits in: s holds 2, p holds 6, d holds 10 and f holds 14. Shell 4 here is 4s² 4p⁶ 4d¹⁰ 4f¹⁴, and 2 + 6 + 10 + 14 is 32.

Nihonium sits in period 7 and has 7 shells. The period number counts the shells.

No one has measured this configuration. Only a few atoms of nihonium have ever existed, so it is predicted from the pattern of the table.

What that means for bonding

The outer shell holds 3 electrons. Those are the ones nihonium can lose, gain or share, so they are the ones that decide what it bonds with.

Only a handful of atoms have ever been made, each lasting seconds or less, so its chemistry is predicted from its place in the table rather than measured.

Properties

State at 25 °C: not known
Physical properties: none measured; no more than a few atoms have ever existed at once

Where it is found

Not found in nature. It is made a few atoms at a time in particle accelerators by fusing lighter nuclei, and each atom decays within seconds to hours.

Discovery and name

Kosuke Morita's team at RIKEN in Japan made an atom of it in 2004 by fusing zinc and bismuth nuclei, and after years of running the experiment saw a third atom in 2012 that confirmed the discovery. It was named in 2016 after Nihon, a Japanese name for Japan.

What it is used for

Research only; its chemistry is barely known.