Thulium

69
Tm
Gruppe
n/a
Periode
6
Blok
f
Protons
Electrons
Neutrons
69
69
100
General Properties
Atomnummer
69
Atommasse
168,93421
Mass Number
169
Kategori
Lantanider
Farve
Silver
Radioactive
Nej
Named after Thule, the earliest name for Scandinavia
Krystalstruktur
Simpel Hexagonal
History
Thulium was discovered by Swedish chemist Per Teodor Cleve in 1879 by looking for impurities in the oxides of other rare earth elements.

The first researcher to obtain nearly pure thulium was Charles James, a British expatriate working on a large scale at New Hampshire College in Durham.

High-purity thulium oxide was first offered commercially in the late 1950s.
Elektroner i hver skal
2, 8, 18, 31, 8, 2
Elektronkonfiguration
[Xe] 4f13 6s2
Tm
Thulium ore occurs most commonly in China
Physical Properties
Tilstandsform
Fast stof
Massefylde
9,321 g/cm3
Smeltepunkt
1818,15 K | 1545 °C | 2813 °F
Kogepunkt
2223,15 K | 1950 °C | 3542 °F
Smeltevarme
16,8 kJ/mol
Fordampningsvarme
250 kJ/mol
Varmefylde
0,16 J/g·K
Abundance in Earth's crust
0,000045%
Abundance in Universe
1×10-8%
Ultrapure
Billede akkrediteringer: Images-of-elements
Ultrapure crystalline thulium
CAS Number
7440-30-4
PubChem CID Number
23961
Atomic Properties
Atomradius
176 pm
Kovalent radius
190 pm
Elektronegativitet
1,25 (Paulings skala)
Ionization Potential
6,1843 eV
Atomic Volume
18,1 cm3/mol
Varmeledningsevne
0,168 W/cm·K
Oxidationstrin
2, 3
Applications
Thulium is used to dope yttrium aluminum garnets used in lasers.

It has also been used in high-temperature superconductors similarly to yttrium.

Thulium has use in ferrites, ceramic magnetic materials that are used in microwave equipment.

Thulium is used in euro banknotes for its blue fluorescence under UV light to defeat counterfeiters.
Thulium is considered to be non-toxic
Isotoper
Stable Isotopes
169Tm
Unstable Isotopes
145Tm, 146Tm, 147Tm, 148Tm, 149Tm, 150Tm, 151Tm, 152Tm, 153Tm, 154Tm, 155Tm, 156Tm, 157Tm, 158Tm, 159Tm, 160Tm, 161Tm, 162Tm, 163Tm, 164Tm, 165Tm, 166Tm, 167Tm, 168Tm, 170Tm, 171Tm, 172Tm, 173Tm, 174Tm, 175Tm, 176Tm, 177Tm, 178Tm, 179Tm