Sm - Samarium
Samarium Element Information, Facts, Properties, Trends, Uses, Comparison with other elements
Samarium is a chemical element with symbol Sm and atomic number 62. It is a moderately hard silvery metal that readily oxidizes in air. Being a typical member of the Lanthanide series, samarium usually assumes the oxidation state +3.
It belongs to group null of the periodic table having trivial name . You can also download Printable Periodic Table of Elements Flashcards for Samarium in a PDF format.
Samarium Facts
Read key information and facts about element Samarium
| Name | Samarium |
| Atomic Number | 62 |
| Atomic Symbol | Sm |
| Atomic Weight | 150.36 |
| Phase | Solid |
| Color | Silver |
| Appearance | silvery white |
| Classification | Lanthanide |
| Natural Occurance | Primordial |
| Group in Periodic Table | - |
| Group Name | |
| Period in Periodic Table | period 6 |
| Block in Periodic Table | f-block |
| Electronic Configuration | [Xe] 4f6 6s2 |
| Electronic Shell Structure (Electrons per shell) | 2, 8, 18, 24, 8, 2 |
| Melting Point | 1345 K |
| Boiling Point | 2076 K |
| CAS Number | CAS7440-19-9 |
How to Locate Samarium on Periodic Table
Periodic table is arranged by atomic number, number of protons in the nucleus which is same as number of electrons. The atomic number increases from left to right. Periodic table starts at top left ( Atomic number 1) and ends at bottom right (atomic number 118). Therefore you can directly look for atomic number 62 to find Samarium on periodic table.
Another way to read periodic table and locate an element is by using group number (column) and period number (row). To locate Samarium on periodic table look for cross section of group - and period 6 in the modern periodic table.
Samarium History
The element Samarium was discovered by P.E.L. de Boisbaudran in year 1879 in France. Samarium was first isolated by P.E.L. de Boisbaudran in 1879. Samarium derived its name from Samarskite, the name of the mineral from which it was first isolated.
| Discovered By | P.E.L. de Boisbaudran |
| Discovery Date | 1879 in France |
| First Isolation | 1879 |
| Isolated by | P.E.L. de Boisbaudran |
Boisbaudran noted a new earth in samarskite and named it samaria after the mineral.
Samarium Uses
Samarium is used as a catalyst for the dehydration and dehydrogenation of ethanol fuels. It can also be used to absorb infrared light rays and in the treatment of cancer.
Samarium Presence: Abundance in Nature and Around Us
The table below shows the abundance of Samarium in Universe, Sun, Meteorites, Earth's Crust, Oceans and Human Body.
| ppb by weight (1ppb =10^-7 %) | ppb by atoms (1ppb =10^-7 %) | |
|---|---|---|
| Abundance in Universe | 5 | 0.04 |
| Abundance in Sun | 1 | 0.01 |
| Abundance in Meteorites | 170 | 20 |
| Abundance in Earth's Crust | 6000 | 820 |
| Abundance in Oceans | 0.00045 | 0.000019 |
| Abundance in Humans | - | - |
Crystal Structure of Samarium
The solid state structure of Samarium is Simple Trigonal.
The Crystal structure can be described in terms of its unit Cell. The unit Cells repeats itself in three dimensional space to form the structure.
Unit Cell Parameters
The unit cell is represented in terms of its lattice parameters, which are the lengths of the cell edges Lattice Constants (a, b and c)
| a | b | c |
|---|---|---|
| 362.1 pm | 362.1 pm | 2625 pm |
and the angles between them Lattice Angles (alpha, beta and gamma).
| alpha | beta | gamma |
|---|---|---|
| π/2 | π/2 | 2 π/3 |
The positions of the atoms inside the unit cell are described by the set of atomic positions ( xi, yi, zi) measured from a reference lattice point.
The symmetry properties of the crystal are described by the concept of space groups. All possible symmetric arrangements of particles in three-dimensional space are described by the 230 space groups (219 distinct types, or 230 if chiral copies are considered distinct.
| Space Group Name | R_ 3m |
| Space Group Number | 166 |
| Crystal Structure | Simple Trigonal |
| Number of atoms per unit cell |
The number of atoms per unit cell in a simple cubic, face-centered cubic and body-centred cubic are 1,4,2 respectively.
Samarium Atomic and Orbital Properties
Samarium atoms have 62 electrons and the electronic shell structure is [2, 8, 18, 24, 8, 2] with Atomic Term Symbol (Quantum Numbers) 7F0.
| Atomic Number | 62 |
| Number of Electrons (with no charge) | 62 |
| Number of Protons | 62 |
| Mass Number | 150 |
| Number of Neutrons | 88 |
| Shell structure (Electrons per energy level) | 2, 8, 18, 24, 8, 2 |
| Electron Configuration | [Xe] 4f6 6s2 |
| Valence Electrons | 4f6 6s2 |
| Valence (Valency) | 3 |
| Main Oxidation States | 3 |
| Oxidation States | 0, 1, 2, 3 |
| Atomic Term Symbol (Quantum Numbers) | 7F0 |
Bohr Atomic Model of Samarium - Electrons per energy level
| n | s | p | d | f |
|---|
Ground State Electronic Configuration of Samarium - neutral Samarium atom
Abbreviated electronic configuration of Samarium
The ground state abbreviated electronic configuration of Neutral Samarium atom is [Xe] 4f6 6s2. The portion of Samarium configuration that is equivalent to the noble gas of the preceding period, is abbreviated as [Xe]. For atoms with many electrons, this notation can become lengthy and so an abbreviated notation is used. This is important as it is the Valence electrons 4f6 6s2, electrons in the outermost shell that determine the chemical properties of the element.
Unabbreviated electronic configuration of neutral Samarium
Complete ground state electronic configuration for the Samarium atom, Unabbreviated electronic configuration
1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f6 6s2
Electrons are filled in atomic orbitals as per the order determined by the Aufbau principle, Pauli Exclusion Principle and Hund’s Rule.
As per the Aufbau principle the electrons will occupy the orbitals having lower energies before occupying higher energy orbitals. According to this principle, electrons are filled in the following order: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p…
The Pauli exclusion principle states that a maximum of two electrons, each having opposite spins, can fit in an orbital.
Hund's rule states that every orbital in a given subshell is singly occupied by electrons before a second electron is filled in an orbital.
Atomic Structure of Samarium
Samarium atomic radius is 238 pm, while it's covalent radius is -.
| Atomic Radius Calculated | 238 pm(2.38 Å) |
| Atomic Radius Empirical | 185 pm (1.85 Å) |
| Atomic Volume | 19.98 cm3/mol |
| Covalent Radius | - |
| Van der Waals Radius | - |
| Neutron Cross Section | 5900 |
| Neutron Mass Absorption | 4.7 |
Spectral Lines of Samarium - Atomic Spectrum of Samarium
A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from an excess or deficiency of photons in a narrow frequency range, compared with the nearby frequencies. Spectral lines are often used to identify atoms and molecules.
Spectral lines are the result of interaction between a quantum system and a single photon. A spectral line may be observed either as an emission line or an absorption line.
Spectral lines are highly atom-specific, and can be used to identify the chemical composition of any medium. Several elements, including helium, thallium, and caesium, were discovered by spectroscopic means. They are widely used to determine the physical conditions of stars and other celestial bodies that cannot be analyzed by other means.
Emission spectrum of Samarium
Absorption spectrum of Samarium
Samarium Chemical Properties: Samarium Ionization Energies and electron affinity
The electron affinity of Samarium is 50 kJ/mol.
| Valence | 3 |
| Electronegativity | 1.17 |
| ElectronAffinity | 50 kJ/mol |
Ionization Energy of Samarium
Ionization energy is the amount of energy required to remove an electron from an atom or molecule.in chemistry, this energy is expresed in kilocalories per mole (kcal/mol) or kilojoules per mole (kJ/mol).
Refer to table below for Ionization energies of Samarium
| Ionization energy number | Enthalpy - kJ/mol |
|---|---|
| 1st | 544.5 |
| 2nd | 1070 |
| 3rd | 2260 |
| 4th | 3990 |
Samarium Physical Properties
Refer to below table for Samarium Physical Properties
| Density | 7.353 g/cm3(when liquid at m.p density is $7.16 g/cm3) |
| Molar Volume | 19.98 cm3/mol |
Elastic Properties
| Young Modulus | 50 |
| Shear Modulus | 20 GPa |
| Bulk Modulus | 38 GPa |
| Poisson Ratio | 0.27 |
Hardness of Samarium - Tests to Measure of Hardness of Element
| Mohs Hardness | - |
| Vickers Hardness | 412 MPa |
| Brinell Hardness | 441 MPa |
Samarium Electrical Properties
Electrical resistivity measures element's electrical resistance or how strongly it resists electric current.The SI unit of electrical resistivity is the ohm-metre (Ω⋅m). While Electrical conductivity is the reciprocal of electrical resistivity. It represents a element's ability to conduct electric current. The SI unit of electrical conductivity is siemens per metre (S/m).
Samarium is a conductor of electricity. Refer to table below for the Electrical properties of Samarium
| Electrical conductors | Conductor |
| Electrical Conductivity | 1100000 S/m |
| Resistivity | 9.4e-7 m Ω |
| Superconducting Point | - |
Samarium Heat and Conduction Properties
| Thermal Conductivity | 13 W/(m K) |
| Thermal Expansion | 0.0000127 /K |
Samarium Magnetic Properties
| Magnetic Type | Paramagnetic |
| Curie Point | - |
| Mass Magnetic Susceptibility | 1.11e-7 m3/kg |
| Molar Magnetic Susceptibility | 1.669e-8 m3/mol |
| Volume Magnetic Susceptibility | 0.00081618 |
Optical Properties of Samarium
| Refractive Index | - |
Acoustic Properties of Samarium
| Speed of Sound | 2130 m/s |
Samarium Thermal Properties - Enthalpies and thermodynamics
Refer to table below for Thermal properties of Samarium
| Melting Point | 1345 K(1071.85 °C, 1961.330 °F) |
| Boiling Point | 2076 K(1802.85 °C, 3277.130 °F) |
| Critical Temperature | - |
| Superconducting Point | - |
Enthalpies of Samarium
| Heat of Fusion | 8.6 kJ/mol |
| Heat of Vaporization | 175 kJ/mol |
| Heat of Combustion | - |
Samarium Isotopes - Nuclear Properties of Samarium
Samarium has 38 isotopes, with between 128 and 165 nucleons. Samarium has 5 stable naturally occuring isotopes.
Isotopes of Samarium - Naturally occurring stable Isotopes: 144Sm, 149Sm, 150Sm, 152Sm, 154Sm.
| Isotope | Z | N | Isotope Mass | % Abundance | T half | Decay Mode |
|---|---|---|---|---|---|---|
| 128Sm | 62 | 66 | 128 | Synthetic | ||
| 129Sm | 62 | 67 | 129 | Synthetic | ||
| 130Sm | 62 | 68 | 130 | Synthetic | ||
| 131Sm | 62 | 69 | 131 | Synthetic | ||
| 132Sm | 62 | 70 | 132 | Synthetic | ||
| 133Sm | 62 | 71 | 133 | Synthetic | ||
| 134Sm | 62 | 72 | 134 | Synthetic | ||
| 135Sm | 62 | 73 | 135 | Synthetic | ||
| 136Sm | 62 | 74 | 136 | Synthetic | ||
| 137Sm | 62 | 75 | 137 | Synthetic | ||
| 138Sm | 62 | 76 | 138 | Synthetic | ||
| 139Sm | 62 | 77 | 139 | Synthetic | ||
| 140Sm | 62 | 78 | 140 | Synthetic | ||
| 141Sm | 62 | 79 | 141 | Synthetic | ||
| 142Sm | 62 | 80 | 142 | Synthetic | ||
| 143Sm | 62 | 81 | 143 | Synthetic | ||
| 144Sm | 62 | 82 | 144 | 3.07% | Stable | N/A |
| 145Sm | 62 | 83 | 145 | Synthetic | ||
| 146Sm | 62 | 84 | 146 | Synthetic | ||
| 147Sm | 62 | 85 | 147 | 14.99% | Stable | N/A |
| 148Sm | 62 | 86 | 148 | 11.24% | Stable | N/A |
| 149Sm | 62 | 87 | 149 | 13.82% | Stable | N/A |
| 150Sm | 62 | 88 | 150 | 7.38% | Stable | |
| 151Sm | 62 | 89 | 151 | Synthetic | ||
| 152Sm | 62 | 90 | 152 | 26.75% | Stable | N/A |
| 153Sm | 62 | 91 | 153 | Synthetic | ||
| 154Sm | 62 | 92 | 154 | 22.75% | Stable | N/A |
| 155Sm | 62 | 93 | 155 | Synthetic | ||
| 156Sm | 62 | 94 | 156 | Synthetic | ||
| 157Sm | 62 | 95 | 157 | Synthetic | ||
| 158Sm | 62 | 96 | 158 | Synthetic | ||
| 159Sm | 62 | 97 | 159 | Synthetic | ||
| 160Sm | 62 | 98 | 160 | Synthetic | ||
| 161Sm | 62 | 99 | 161 | Synthetic | ||
| 162Sm | 62 | 100 | 162 | Synthetic | ||
| 163Sm | 62 | 101 | 163 | Synthetic | ||
| 164Sm | 62 | 102 | 164 | Synthetic | ||
| 165Sm | 62 | 103 | 165 | Synthetic |
Regulatory and Health - Health and Safety Parameters and Guidelines
The United States Department of Transportation (DOT) identifies hazard class of all dangerous elements/goods/commodities either by its class (or division) number or name. The DOT has divided these materials into nine different categories, known as Hazard Classes.
| DOT Numbers | 1325 |
| DOT Hazard Class | 4.1 |
NFPA 704 is a Standard System for the Identification of the Hazards of Materials for Emergency Response. NFPA is a standard maintained by the US based National Fire Protection Association.
The health (blue), flammability (red), and reactivity (yellow) rating all use a numbering scale ranging from 0 to 4. A value of zero means that the element poses no hazard; a rating of four indicates extreme danger.
| NFPA Fire Rating | 1 | Flash Points Above 93.3°C (200°F) |
| NFPA Health Rating | 1 | Flash Points Above 93.3°C (200°F) |
| NFPA Reactivity Rating | 1 | Flash Points Above 93.3°C (200°F) |
| NFPA Hazards |
| Autoignition Point | 150 °C |
| Flashpoint | - |
Database Search
List of unique identifiers to search the element in various chemical registry databases
| Database | Identifier number |
|---|---|
| CAS Number - Chemical Abstracts Service (CAS) | CAS7440-19-9 |
| RTECS Number | - |
| CID Number | CID23951 |
| Gmelin Number | - |
| NSC Number | - |
Compare Samarium with other elements
Compare Samarium with Group , Period 6 and Lanthanide elements of the periodic table.
Compare Samarium with all Group elements
Compare Samarium with all Period 6 elements
Compare Samarium with all Lanthanide elements
Frequently Asked Questions (FAQ)
Find the answers to the most frequently asked questions about Samarium