Symbol
Sm
Tm
Group Number
33
0
17
👆🏻
Period Number
66
2
7
👆🏻
Block
f block
f block
Element Family
Lanthanide
Lanthanide
CAS Number
74401997440304
7429905
54386242
👆🏻
Space Group Name
R_ 3m
P63/mmc
Space Group Number
166.00194.00
11
276
👆🏻
Interesting Facts
- Samarium metals helps stimulating body metabolism.
- Samarium metals was 1st observed by Jean Charles Galissard de Marignac in Dydimia in 1853.
- Thulium metal can resist corrosion due to dry air .
- Only Tm-169 isotope of Thulium metal occur naturally.
Sources
Found in Minerals, Mining, Ores of Minerals
Found in Minerals, Mining, Ores of Minerals
History
Who Discovered
Lecoq de Boisbaudran
Per Teodor Cleve
Discovery
In 1879
In 1879
Abundance
Abundance In Universe
0.00 %0.00 %
0
0.11
👆🏻
Abundance In Sun
0.00 %0.00 %
0
0.1
👆🏻
Abundance In Meteorites
0.00 %0.00 %
0
22
👆🏻
Abundance In Earth's Crust
0.00 %0.00 %
1E-37
8.1
👆🏻
Abundance In Oceans
0.00 %0.00 %
0
1.1
👆🏻
Abundance In Humans
0.00 %0.00 %
0
1.4
👆🏻
Uses & Benefits
- Magnets of Samarium cobalt alloy are stronger than that of Iron and hence, they are used in microwave application.
- Samarium metal also used in optical lasers and infrared absorbing glasses and as a neutron absorber.
- Thulium metal produces isotopes that emits X-rays. This isotope is used in X-ray machine.
-
Thulium element is also used in Surgical equipment like laser.
Industrial Uses
Aerospace Industry, Automobile Industry, Chemical Industry, Electrical Industry, Electronic Industry
-
Medical Uses
-
-
Other Uses
Alloys, In Nuclear Reactors
Alloys, Nuclear Research, Research Purposes
Biological Properties
Toxicity
Slightly Toxic
-
Present in Human Body
✔
✘
✔
✘
In Blood
0.01 Blood/mg dm-30.00 Blood/mg dm-3
0
1970
👆🏻
In Bone
0.00 p.p.m.0.00 p.p.m.
0
170000
👆🏻
Melting Point
1,072.00 °C1,545.00 °C
-38.83
3410
👆🏻
Boiling Point
1,900.00 °C1,730.00 °C
0
5660
👆🏻
Appearance
Physical State
Solid
Solid
Color
Silvery White
Silvery Gray
Luster
Lustrous
Metallic
Hardness
Mohs Hardness
5.502.25
0.2
8.5
👆🏻
Brinell Hardness
441.00 MPa471.00 MPa
0.14
3490
👆🏻
Vickers Hardness
412.00 MPa520.00 MPa
0
3920
👆🏻
Speed of Sound
2,130.00 m/s2,760.00 m/s
818
16200
👆🏻
Optical Properties
Refractive Index
1.801.60
0.155
3.41
👆🏻
Reflectivity
65.00 %35.00 %
5
97
👆🏻
Allotropes
✔
✘
✔
✘
α Allotropes
-
-
β Allotropes
-
-
γ Allotropes
-
-
Chemical Formula
Sm
Tm
Isotopes
Known Isotopes
3032
0
38
👆🏻
Electronegativity
Pauling Electronegativity
1.171.25
0
2.6
👆🏻
Sanderson Electronegativity
1.171.25
0.22
2.56
👆🏻
Allred Rochow Electronegativity
1.071.11
0.86
1.9
👆🏻
Mulliken-Jaffe Electronegativity
1.171.25
0.62
2.48
👆🏻
Allen Electronegativity
1.171.25
0.659
2.7
👆🏻
Electropositivity
Pauling Electropositivity
2.832.75
1.46
3.3
👆🏻
Ionization Energies
1st Energy Level
544.50 kJ/mol596.70 kJ/mol
375.7
26130
👆🏻
2nd Energy Level
1,070.00 kJ/mol1,160.00 kJ/mol
392.8
28750
👆🏻
3rd Energy Level
2,260.00 kJ/mol2,285.00 kJ/mol
392.8
34230
👆🏻
4th Energy Level
3,990.00 kJ/mol4,120.00 kJ/mol
375.7
37066
👆🏻
5th Energy Level
5,445.00 kJ/mol5,960.00 kJ/mol
392
97510
👆🏻
6th Energy Level
5,445.00 kJ/mol5,960.00 kJ/mol
1007
105800
👆🏻
7th Energy level
5,445.00 kJ/mol5,960.00 kJ/mol
1007
114300
👆🏻
8th Energy Level
5,400.00 kJ/mol5,960.00 kJ/mol
730
125300
👆🏻
9th Energy Level
5,440.00 kJ/mol5,960.00 kJ/mol
1007
134700
👆🏻
10th Energy Level
5,445.00 kJ/mol5,960.00 kJ/mol
392
144300
👆🏻
11th Energy Level
5,445.00 kJ/mol5,960.00 kJ/mol
392
169988
👆🏻
12th Energy Level
5,440.00 kJ/mol5,960.00 kJ/mol
0
189368
👆🏻
13th Energy Level
5,445.00 kJ/mol5,960.00 kJ/mol
1007
76015
👆🏻
14th Energy Level
5,450.00 kJ/mol5,960.00 kJ/mol
380
86450
👆🏻
15th Energy Level
54,450.00 kJ/mol59,600.00 kJ/mol
33000
100700
👆🏻
16th Energy Level
54,400.00 kJ/mol59,600.00 kJ/mol
375.7
109480
👆🏻
17th Energy Level
544.50 kJ/mol596.70 kJ/mol
375.7
122200
👆🏻
18th Energy Level
5,445.00 kJ/mol5,960.00 kJ/mol
0
134810
👆🏻
19th Energy Level
544.50 kJ/mol596.00 kJ/mol
375.7
148700
👆🏻
20th Energy Level
624.00 kJ/mol596.00 kJ/mol
0
171200
👆🏻
21st Energy Level
544.50 kJ/mol596.70 kJ/mol
375.7
179100
👆🏻
22nd Energy Level
624.00 kJ/mol596.00 kJ/mol
330
184900
👆🏻
23rd Energy Level
544.50 kJ/mol596.70 kJ/mol
357.6
198800
👆🏻
24th Energy Level
544.50 kJ/mol596.00 kJ/mol
297.3
195200
👆🏻
25th Energy Level
544.00 kJ/mol596.00 kJ/mol
0
121900
👆🏻
26th Energy Level
544.50 kJ/mol596.70 kJ/mol
357.6
127700
👆🏻
27th Energy Level
544.50 kJ/mol596.70 kJ/mol
0
133800
👆🏻
28th Energy Level
544.50 kJ/mol596.70 kJ/mol
297.3
139800
👆🏻
29th Energy Level
544.50 kJ/mol596.00 kJ/mol
0
148100
👆🏻
30th Energy Level
544.00 kJ/mol596.70 kJ/mol
0
154500
👆🏻
Electrochemical Equivalent
1.87 g/amp-hr2.10 g/amp-hr
0.16812
8.3209
👆🏻
Electron Work Function
2.70 eV2.40 eV
2.14
6
👆🏻
Other Chemical Properties
Ionization, Radioactive Isotopes
Ionization, Radioactive Isotopes, Solubility
Atomic Number
6269
3
117
👆🏻
Electron Configuration
[Xe] 4f6 6s2
[Xe] 4f13 6s2
Crystal Structure
Rhombohedral (RHO)
Hexagonal Close Packed (HCP)
Crystal Lattice
Atom
Number of Protons
6269
3
117
👆🏻
Number of Neutrons
88100
4
285
👆🏻
Number of Electrons
6269
3
117
👆🏻
Radius of an Atom
Atomic Radius
180.00 pm176.00 pm
0
348
👆🏻
Covalent Radius
198.00 pm160.00 pm
0
260
👆🏻
Van der Waals Radius
229.00 pm227.00 pm
0
348
👆🏻
Atomic Weight
150.36 amu168.93 amu
6.94
294
👆🏻
Atomic Volume
19.95 cm3/mol18.10 cm3/mol
1.39
71.07
👆🏻
Adjacent Atomic Numbers
Previous Element
Next Element
Valence Electron Potential
44.80 (-eV)49.70 (-eV)
0
392.42
👆🏻
Lattice Constant
362.10 pm353.75 pm
0
891.25
👆🏻
Lattice Angles
π/2, π/2, 2 π/3
π/2, π/2, 2 π/3
Lattice C/A Ratio
1.621.57
0.423
1.9
👆🏻
Density
Density At Room Temperature
7.52 g/cm39.32 g/cm3
0.534
40.7
👆🏻
Density When Liquid (at m.p.)
7.16 g/cm38.56 g/cm3
0.512
41
👆🏻
Tensile Strength
50.00 MPa69.00 MPa
0.1
11000
👆🏻
Viscosity
0.000.00
1.5E-05
0.0035
👆🏻
Vapor Pressure
Vapor Pressure at 1000 K
0.94 (Pa)0.06 (Pa)
0
121
👆🏻
Vapor Pressure at 2000 K
0.00 (Pa)0.00 (Pa)
0
774
👆🏻
Elasticity properties
Shear Modulus
19.50 GPa30.50 GPa
1.3
222
👆🏻
Bulk Modulus
37.80 GPa44.50 GPa
0
462
👆🏻
Young's Modulus
49.70 GPa74.00 GPa
0
528
👆🏻
Poisson Ratio
0.270.21
0.032
0.47
👆🏻
Other Mechanical Properties
-
Ductile, Malleable
Magnetic Characteristics
Specific Gravity
7.529.32
0.53
4500
👆🏻
Magnetic Ordering
Paramagnetic
Paramagnetic
Permeability
0.00 H/m0.00 H/m
1.25643E-06
0.0063
👆🏻
Susceptibility
0.000.00
-0.000166
200000
👆🏻
Electrical Properties
Electrical Property
Conductor
Conductor
Resistivity
0.94 nΩ·m676.00 nΩ·m
0.1
961
👆🏻
Electrical Conductivity
0.01 106/cm Ω0.02 106/cm Ω
0
0.63
👆🏻
Electron Affinity
50.00 kJ/mol50.00 kJ/mol
0
222.8
👆🏻
Specific Heat
0.20 J/(kg K)0.16 J/(kg K)
0.1
3.6
👆🏻
Molar Heat Capacity
29.54 J/mol·K27.03 J/mol·K
13.1
62.7
👆🏻
Thermal Conductivity
13.30 W/m·K16.90 W/m·K
0
429
👆🏻
Critical Temperature
1,345.00 K1,818.00 K
26.3
3695
👆🏻
Thermal Expansion
12.70 µm/(m·K)13.30 µm/(m·K)
4.5
97
👆🏻
Enthalpy
Enthalpy of Vaporization
166.40 kJ/mol191.00 kJ/mol
7.32
799.1
👆🏻
Enthalpy of Fusion
8.62 kJ/mol16.80 kJ/mol
2.1
35.23
👆🏻
Enthalpy of Atomization
209.00 kJ/mol247.00 kJ/mol
61.5
837
👆🏻
Standard Molar Entropy
69.60 J/mol.K74.00 J/mol.K
9.5
198.1
👆🏻