Symbol
Cm
Es
Group Number
313
0
17
👆🏻
Period Number
77
2
7
👆🏻
Block
f block
f block
Element Family
Actinide
Actinide
CAS Number
74405197429927
7429905
54386242
👆🏻
Space Group Name
-
-
Space Group Number
225.00194.00
11
276
👆🏻
Interesting Facts
- Curium metal does not occur free in nature.
- Curium metal is a synthetically produced metal.
- Einsteinium is the transuranic element found in US.
- Only 0.01 mg of Einsteinium was synthesized in 1961.
Sources
Bombarding Plutonium with Helium Ions
Made by Bombarding Uranium with Neutrons
History
Who Discovered
Glenn T. Seaborg, Ralph A. James, Albert Ghiorso
Lawrence Berkeley National Laboratory
Discovery
In 1944
In 1952
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
1.1
👆🏻
Abundance In Humans
0.00 %0.00 %
0
1.4
👆🏻
Uses & Benefits
- Curium metal is used to provide power to electrical equipment for space missions.
- Currently known uses of Einsteinium metal are limited to research purpose only.
Industrial Uses
-
-
Medical Uses
-
-
Other Uses
Research Purposes
Alloys, Nuclear Research, Research Purposes
Biological Properties
Toxicity
-
Toxic
Present in Human Body
✔
✘
✔
✘
In Blood
0.00 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
1,340.00 °C860.00 °C
-38.83
3410
👆🏻
Boiling Point
3,110.00 °C996.00 °C
0
5660
👆🏻
Appearance
Physical State
Solid
Solid
Color
Silver
Silver
Luster
Metallic
-
Hardness
Mohs Hardness
2.006.00
0.2
8.5
👆🏻
Brinell Hardness
320.00 MPa240.00 MPa
0.14
3490
👆🏻
Vickers Hardness
461.00 MPa550.00 MPa
0
3920
👆🏻
Speed of Sound
2,260.00 m/s2,850.00 m/s
818
16200
👆🏻
Optical Properties
Refractive Index
1.301.30
0.155
3.41
👆🏻
Reflectivity
60.00 %63.00 %
5
97
👆🏻
Allotropes
✔
✘
✔
✘
α Allotropes
-
-
β Allotropes
-
-
γ Allotropes
-
-
Chemical Formula
Cm
Es
Isotopes
Known Isotopes
1516
0
38
👆🏻
Electronegativity
Pauling Electronegativity
1.301.54
0
2.6
👆🏻
Sanderson Electronegativity
1.301.30
0.22
2.56
👆🏻
Allred Rochow Electronegativity
1.201.20
0.86
1.9
👆🏻
Mulliken-Jaffe Electronegativity
1.301.30
0.62
2.48
👆🏻
Allen Electronegativity
1.301.30
0.659
2.7
👆🏻
Electropositivity
Pauling Electropositivity
2.702.70
1.46
3.3
👆🏻
Ionization Energies
1st Energy Level
581.00 kJ/mol619.00 kJ/mol
375.7
26130
👆🏻
2nd Energy Level
1,196.00 kJ/mol1,216.00 kJ/mol
392.8
28750
👆🏻
3rd Energy Level
2,026.00 kJ/mol2,334.00 kJ/mol
392.8
34230
👆🏻
4th Energy Level
3,550.00 kJ/mol3,734.00 kJ/mol
375.7
37066
👆🏻
5th Energy Level
5,810.00 kJ/mol6,190.00 kJ/mol
392
97510
👆🏻
6th Energy Level
5,810.00 kJ/mol6,190.00 kJ/mol
1007
105800
👆🏻
7th Energy level
5,810.00 kJ/mol6,190.00 kJ/mol
1007
114300
👆🏻
8th Energy Level
5,810.00 kJ/mol6,190.00 kJ/mol
730
125300
👆🏻
9th Energy Level
6,690.00 kJ/mol4,520.00 kJ/mol
1007
134700
👆🏻
10th Energy Level
5,810.00 kJ/mol6,190.00 kJ/mol
392
144300
👆🏻
11th Energy Level
5,810.00 kJ/mol6,190.00 kJ/mol
392
169988
👆🏻
12th Energy Level
58,100.00 kJ/mol61,900.00 kJ/mol
0
189368
👆🏻
13th Energy Level
5,810.00 kJ/mol6,190.00 kJ/mol
1007
76015
👆🏻
14th Energy Level
5,810.00 kJ/mol6,190.00 kJ/mol
380
86450
👆🏻
15th Energy Level
58,100.00 kJ/mol61,900.00 kJ/mol
33000
100700
👆🏻
16th Energy Level
58,100.00 kJ/mol61,900.00 kJ/mol
375.7
109480
👆🏻
17th Energy Level
581.00 kJ/mol619.00 kJ/mol
375.7
122200
👆🏻
18th Energy Level
5,810.00 kJ/mol6,190.00 kJ/mol
0
134810
👆🏻
19th Energy Level
581.00 kJ/mol619.00 kJ/mol
375.7
148700
👆🏻
20th Energy Level
581.00 kJ/mol619.00 kJ/mol
0
171200
👆🏻
21st Energy Level
5,810.00 kJ/mol6,190.00 kJ/mol
375.7
179100
👆🏻
22nd Energy Level
581.00 kJ/mol619.00 kJ/mol
330
184900
👆🏻
23rd Energy Level
5,810.00 kJ/mol6,190.00 kJ/mol
357.6
198800
👆🏻
24th Energy Level
581.00 kJ/mol619.40 kJ/mol
297.3
195200
👆🏻
25th Energy Level
581.00 kJ/mol619.00 kJ/mol
0
121900
👆🏻
26th Energy Level
581.00 kJ/mol619.40 kJ/mol
357.6
127700
👆🏻
27th Energy Level
581.00 kJ/mol619.40 kJ/mol
0
133800
👆🏻
28th Energy Level
581.00 kJ/mol619.40 kJ/mol
297.3
139800
👆🏻
29th Energy Level
581.00 kJ/mol619.40 kJ/mol
0
148100
👆🏻
30th Energy Level
581.00 kJ/mol619.40 kJ/mol
0
154500
👆🏻
Electrochemical Equivalent
3.07 g/amp-hr4.74 g/amp-hr
0.16812
8.3209
👆🏻
Electron Work Function
4.50 eV4.90 eV
2.14
6
👆🏻
Other Chemical Properties
Ionization, Radioactive Isotopes
Ionization, Radioactive Isotopes, Radioactivity
Atomic Number
9699
3
117
👆🏻
Electron Configuration
[Rn] 5f7 6d1 7s2
[Rn] 5f11 7s2
Crystal Structure
Double Hexagonal Close Packed (DHCP)
Face Centered Cubic (FCC)
Crystal Lattice
Atom
Number of Protons
9699
3
117
👆🏻
Number of Neutrons
151153
4
285
👆🏻
Number of Electrons
9699
3
117
👆🏻
Radius of an Atom
Atomic Radius
174.00 pm186.00 pm
0
348
👆🏻
Covalent Radius
169.00 pm186.00 pm
0
260
👆🏻
Van der Waals Radius
200.00 pm0.00 pm
0
348
👆🏻
Atomic Weight
247.00 amu252.00 amu
6.94
294
👆🏻
Atomic Volume
18.28 cm3/mol17.04 cm3/mol
1.39
71.07
👆🏻
Adjacent Atomic Numbers
Previous Element
Next Element
Valence Electron Potential
44.50 (-eV)0.00 (-eV)
0
392.42
👆🏻
Lattice Constant
336.25 pm582.00 pm
0
891.25
👆🏻
Lattice Angles
-
-
Lattice C/A Ratio
1.671.29
0.423
1.9
👆🏻
Density
Density At Room Temperature
13.51 g/cm38.84 g/cm3
0.534
40.7
👆🏻
Density When Liquid (at m.p.)
13.85 g/cm38.84 g/cm3
0.512
41
👆🏻
Tensile Strength
350.00 MPa0.10 MPa
0.1
11000
👆🏻
Viscosity
0.000.00
1.5E-05
0.0035
👆🏻
Vapor Pressure
Vapor Pressure at 1000 K
0.00 (Pa)0.00 (Pa)
0
121
👆🏻
Vapor Pressure at 2000 K
0.00 (Pa)0.00 (Pa)
0
774
👆🏻
Elasticity properties
Shear Modulus
32.00 GPa30.00 GPa
1.3
222
👆🏻
Bulk Modulus
40.00 GPa40.00 GPa
0
462
👆🏻
Young's Modulus
0.00 GPa0.00 GPa
0
528
👆🏻
Poisson Ratio
0.350.33
0.032
0.47
👆🏻
Other Mechanical Properties
-
-
Magnetic Characteristics
Specific Gravity
13.518.84
0.53
4500
👆🏻
Magnetic Ordering
Antiferromagnetic
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
-
-
Resistivity
1.25 nΩ·m6.30 nΩ·m
0.1
961
👆🏻
Electrical Conductivity
0.13 106/cm Ω0.14 106/cm Ω
0
0.63
👆🏻
Electron Affinity
0.00 kJ/mol0.00 kJ/mol
0
222.8
👆🏻
Specific Heat
0.10 J/(kg K)0.10 J/(kg K)
0.1
3.6
👆🏻
Molar Heat Capacity
27.50 J/mol·K27.20 J/mol·K
13.1
62.7
👆🏻
Thermal Conductivity
11.00 W/m·K0.00 W/m·K
0
429
👆🏻
Critical Temperature
1,340.00 K1,133.00 K
26.3
3695
👆🏻
Thermal Expansion
11.60 µm/(m·K)13.50 µm/(m·K)
4.5
97
👆🏻
Enthalpy
Enthalpy of Vaporization
331.60 kJ/mol323.80 kJ/mol
7.32
799.1
👆🏻
Enthalpy of Fusion
15.00 kJ/mol14.80 kJ/mol
2.1
35.23
👆🏻
Enthalpy of Atomization
--
61.5
837
👆🏻
Standard Molar Entropy
52.50 J/mol.K63.00 J/mol.K
9.5
198.1
👆🏻