మూస:Infobox thulium

థూలియం, ₀₀Tm
థూలియం
Pronunciation	/ˈθjuːliəm/ (THEW-lee-əm)
Appearance	silvery gray
Standard atomic weight Ar°(Tm)
	168.934219±0.000005; 168.93±0.01 (abridged);
థూలియం in the periodic table
Group	f-block groups (no number)
Period	period 6
Block
Electrons per shell	2, 8, 18, 31, 8, 2
Physical properties
Phase at STP	solid
Melting point	1818 K (1545 °C, 2813 °F)
Boiling point	2223 K (1950 °C, 3542 °F)
Density (near r.t.)	9.32 g/cm3
when liquid (at m.p.)	8.56 g/cm3
Heat of fusion	16.84 kJ/mol
Heat of vaporization	247 kJ/mol
Molar heat capacity	27.03 J/(mol·K)
Atomic properties
Oxidation states	0, +1, +2, +3 (a basic oxide)
Electronegativity	Pauling scale: 1.25
Atomic radius	empirical: 176 pm
Covalent radius	190±10 pm
Other properties
Natural occurrence	primordial
Crystal structure	hexagonal close-packed (hcp)
Thermal expansion	(r.t.) (poly); 13.3 µm/(m⋅K)
Thermal conductivity	16.9 W/(m⋅K)
Electrical resistivity	(r.t.) (poly) 676 n Ω⋅m
Magnetic ordering	paramagnetic at 300 K
Young's modulus	74.0 GPa
Shear modulus	30.5 GPa
Bulk modulus	44.5 GPa
Poisson ratio	0.213
Vickers hardness	520 MPa
Brinell hardness	471 MPa
CAS Number	7440-30-4
History
Discovery	Per Teodor Cleve (1879)
First isolation	Per Teodor Cleve (1879)
Isotopes of థూలియం v; e;
	Template:infobox థూలియం isotopes does not exist
	Category: థూలియం; view; talk; edit; \| references

References

↑ "Standard Atomic Weights: Thulium". CIAAW. 2021.
↑ Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; et al. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". Pure and Applied Chemistry (in ఇంగ్లీష్). doi:10.1515/pac-2019-0603. ISSN 1365-3075.
↑ Yttrium and all lanthanides except Ce and Pm have been observed in the oxidation state 0 in bis(1,3,5-tri-t-butylbenzene) complexes, see Cloke, F. Geoffrey N. (1993). "Zero Oxidation State Compounds of Scandium, Yttrium, and the Lanthanides". Chem. Soc. Rev. 22: 17–24. doi:10.1039/CS9932200017. and Arnold, Polly L.; Petrukhina, Marina A.; Bochenkov, Vladimir E.; Shabatina, Tatyana I.; Zagorskii, Vyacheslav V.; Cloke (2003-12-15). "Arene complexation of Sm, Eu, Tm and Yb atoms: a variable temperature spectroscopic investigation". Journal of Organometallic Chemistry. 688 (1–2): 49–55. doi:10.1016/j.jorganchem.2003.08.028.
↑ La(I), Pr(I), Tb(I), Tm(I), and Yb(I) have been observed in MB₈⁻ clusters; see Li, Wan-Lu; Chen, Teng-Teng; Chen, Wei-Jia; Li, Jun; Wang, Lai-Sheng (2021). "Monovalent lanthanide(I) in borozene complexes". Nature Communications. 12 (1): 6467. doi:10.1038/s41467-021-26785-9. PMC 8578558. PMID 34753931.