Symbol
Ho
Sm
Group Number
33
0
17
👆🏻
Period Number
66
2
7
👆🏻
Block
f block
f block
Element Family
Lanthanide
Lanthanide
CAS Number
74406007440199
7429905
54386242
👆🏻
Space Group Name
P63/mmc
R_ 3m
Space Group Number
194.00166.00
11
276
👆🏻
Interesting Facts
- Holmium metal is very soft and malleable.
- Holmium metal is well known for its corrosion resistivity.
- Samarium metals helps stimulating body metabolism.
- Samarium metals was 1st observed by Jean Charles Galissard de Marignac in Dydimia in 1853.
Sources
Found in Minerals, Mining, Ores of Minerals
Found in Minerals, Mining, Ores of Minerals
History
Who Discovered
Marc Delafontaine
Lecoq de Boisbaudran
Discovery
In 1878
In 1879
Abundance
Abundance In Universe
0.00 %0.00 %
0
0.11
👆🏻
Abundance In Sun
-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
- Holmium metal has an ability to absorb neutrons, so this metal is used in nuclear reactors to keep the chain reactions of elements under control.
-
Alloys of Holmium are used to produce Magnet.
- 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.
Industrial Uses
-
Aerospace Industry, Automobile Industry, Chemical Industry, Electrical Industry, Electronic Industry
Medical Uses
-
-
Other Uses
Alloys, Nuclear Research
Alloys, In Nuclear Reactors
Biological Properties
Toxicity
Low Toxic
Slightly Toxic
Present in Human Body
✔
✘
✔
✘
In Blood
0.00 Blood/mg dm-30.01 Blood/mg dm-3
0
1970
👆🏻
In Bone
0.00 p.p.m.0.00 p.p.m.
0
170000
👆🏻
Melting Point
1,461.00 °C1,072.00 °C
-38.83
3410
👆🏻
Boiling Point
2,600.00 °C1,900.00 °C
0
5660
👆🏻
Appearance
Physical State
Solid
Solid
Color
Silvery White
Silvery White
Luster
Metallic
Lustrous
Hardness
Mohs Hardness
4.005.50
0.2
8.5
👆🏻
Brinell Hardness
746.00 MPa441.00 MPa
0.14
3490
👆🏻
Vickers Hardness
481.00 MPa412.00 MPa
0
3920
👆🏻
Speed of Sound
2,760.00 m/s2,130.00 m/s
818
16200
👆🏻
Optical Properties
Refractive Index
1.671.80
0.155
3.41
👆🏻
Reflectivity
67.00 %65.00 %
5
97
👆🏻
Allotropes
✔
✘
✔
✘
α Allotropes
-
-
β Allotropes
-
-
γ Allotropes
-
-
Chemical Formula
Ho
Sm
Isotopes
Known Isotopes
3430
0
38
👆🏻
Electronegativity
Pauling Electronegativity
1.231.17
0
2.6
👆🏻
Sanderson Electronegativity
1.231.17
0.22
2.56
👆🏻
Allred Rochow Electronegativity
1.101.07
0.86
1.9
👆🏻
Mulliken-Jaffe Electronegativity
1.231.17
0.62
2.48
👆🏻
Allen Electronegativity
1.231.17
0.659
2.7
👆🏻
Electropositivity
Pauling Electropositivity
2.772.83
1.46
3.3
👆🏻
Ionization Energies
1st Energy Level
581.00 kJ/mol544.50 kJ/mol
375.7
26130
👆🏻
2nd Energy Level
1,140.00 kJ/mol1,070.00 kJ/mol
392.8
28750
👆🏻
3rd Energy Level
2,204.00 kJ/mol2,260.00 kJ/mol
392.8
34230
👆🏻
4th Energy Level
4,100.00 kJ/mol3,990.00 kJ/mol
375.7
37066
👆🏻
5th Energy Level
5,810.00 kJ/mol5,445.00 kJ/mol
392
97510
👆🏻
6th Energy Level
5,810.00 kJ/mol5,445.00 kJ/mol
1007
105800
👆🏻
7th Energy level
5,810.00 kJ/mol5,445.00 kJ/mol
1007
114300
👆🏻
8th Energy Level
5,810.00 kJ/mol5,400.00 kJ/mol
730
125300
👆🏻
9th Energy Level
6,500.00 kJ/mol5,440.00 kJ/mol
1007
134700
👆🏻
10th Energy Level
6,500.00 kJ/mol5,445.00 kJ/mol
392
144300
👆🏻
11th Energy Level
5,810.00 kJ/mol5,445.00 kJ/mol
392
169988
👆🏻
12th Energy Level
5,810.00 kJ/mol5,440.00 kJ/mol
0
189368
👆🏻
13th Energy Level
5,810.00 kJ/mol5,445.00 kJ/mol
1007
76015
👆🏻
14th Energy Level
5,810.00 kJ/mol5,450.00 kJ/mol
380
86450
👆🏻
15th Energy Level
58,100.00 kJ/mol54,450.00 kJ/mol
33000
100700
👆🏻
16th Energy Level
581.00 kJ/mol54,400.00 kJ/mol
375.7
109480
👆🏻
17th Energy Level
581.00 kJ/mol544.50 kJ/mol
375.7
122200
👆🏻
18th Energy Level
5,810.00 kJ/mol5,445.00 kJ/mol
0
134810
👆🏻
19th Energy Level
581.00 kJ/mol544.50 kJ/mol
375.7
148700
👆🏻
20th Energy Level
581.00 kJ/mol624.00 kJ/mol
0
171200
👆🏻
21st Energy Level
581.00 kJ/mol544.50 kJ/mol
375.7
179100
👆🏻
22nd Energy Level
581.00 kJ/mol624.00 kJ/mol
330
184900
👆🏻
23rd Energy Level
5,810.00 kJ/mol544.50 kJ/mol
357.6
198800
👆🏻
24th Energy Level
581.00 kJ/mol544.50 kJ/mol
297.3
195200
👆🏻
25th Energy Level
581.00 kJ/mol544.00 kJ/mol
0
121900
👆🏻
26th Energy Level
581.00 kJ/mol544.50 kJ/mol
357.6
127700
👆🏻
27th Energy Level
584.70 kJ/mol544.50 kJ/mol
0
133800
👆🏻
28th Energy Level
581.00 kJ/mol544.50 kJ/mol
297.3
139800
👆🏻
29th Energy Level
584.70 kJ/mol544.50 kJ/mol
0
148100
👆🏻
30th Energy Level
581.00 kJ/mol544.00 kJ/mol
0
154500
👆🏻
Electrochemical Equivalent
2.02 g/amp-hr1.87 g/amp-hr
0.16812
8.3209
👆🏻
Electron Work Function
4.90 eV2.70 eV
2.14
6
👆🏻
Other Chemical Properties
Chemical Stability, Anti Corrosion, Ionization, Radioactive Isotopes, Solubility
Ionization, Radioactive Isotopes
Atomic Number
6762
3
117
👆🏻
Electron Configuration
[Xe] 4f11 6s2
[Xe] 4f6 6s2
Crystal Structure
Hexagonal Close Packed (HCP)
Rhombohedral (RHO)
Crystal Lattice
Atom
Number of Protons
6762
3
117
👆🏻
Number of Neutrons
9888
4
285
👆🏻
Number of Electrons
6762
3
117
👆🏻
Radius of an Atom
Atomic Radius
176.00 pm180.00 pm
0
348
👆🏻
Covalent Radius
192.00 pm198.00 pm
0
260
👆🏻
Van der Waals Radius
216.00 pm229.00 pm
0
348
👆🏻
Atomic Weight
164.93 amu150.36 amu
6.94
294
👆🏻
Atomic Volume
18.70 cm3/mol19.95 cm3/mol
1.39
71.07
👆🏻
Adjacent Atomic Numbers
Previous Element
Next Element
Valence Electron Potential
47.90 (-eV)44.80 (-eV)
0
392.42
👆🏻
Lattice Constant
357.73 pm362.10 pm
0
891.25
👆🏻
Lattice Angles
π/2, π/2, 2 π/3
π/2, π/2, 2 π/3
Lattice C/A Ratio
1.571.62
0.423
1.9
👆🏻
Density
Density At Room Temperature
8.79 g/cm37.52 g/cm3
0.534
40.7
👆🏻
Density When Liquid (at m.p.)
8.34 g/cm37.16 g/cm3
0.512
41
👆🏻
Tensile Strength
270.00 MPa50.00 MPa
0.1
11000
👆🏻
Viscosity
0.000.00
1.5E-05
0.0035
👆🏻
Vapor Pressure
Vapor Pressure at 1000 K
0.00 (Pa)0.94 (Pa)
0
121
👆🏻
Vapor Pressure at 2000 K
0.00 (Pa)0.00 (Pa)
0
774
👆🏻
Elasticity properties
Shear Modulus
26.30 GPa19.50 GPa
1.3
222
👆🏻
Bulk Modulus
40.20 GPa37.80 GPa
0
462
👆🏻
Young's Modulus
64.80 GPa49.70 GPa
0
528
👆🏻
Poisson Ratio
0.230.27
0.032
0.47
👆🏻
Other Mechanical Properties
Ductile, Malleable, Sectile
-
Magnetic Characteristics
Specific Gravity
8.807.52
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
814.00 nΩ·m0.94 nΩ·m
0.1
961
👆🏻
Electrical Conductivity
0.01 106/cm Ω0.01 106/cm Ω
0
0.63
👆🏻
Electron Affinity
50.00 kJ/mol50.00 kJ/mol
0
222.8
👆🏻
Specific Heat
0.16 J/(kg K)0.20 J/(kg K)
0.1
3.6
👆🏻
Molar Heat Capacity
27.15 J/mol·K29.54 J/mol·K
13.1
62.7
👆🏻
Thermal Conductivity
16.20 W/m·K13.30 W/m·K
0
429
👆🏻
Critical Temperature
1,747.00 K1,345.00 K
26.3
3695
👆🏻
Thermal Expansion
11.20 µm/(m·K)12.70 µm/(m·K)
4.5
97
👆🏻
Enthalpy
Enthalpy of Vaporization
241.00 kJ/mol166.40 kJ/mol
7.32
799.1
👆🏻
Enthalpy of Fusion
11.76 kJ/mol8.62 kJ/mol
2.1
35.23
👆🏻
Enthalpy of Atomization
301.00 kJ/mol209.00 kJ/mol
61.5
837
👆🏻
Standard Molar Entropy
75.30 J/mol.K69.60 J/mol.K
9.5
198.1
👆🏻