Sm - Samarium

Samarium was discovered by Lecoq de Boisbaudrain in 1879 in Paris.

Atomic number - 62 Density g/mL 7 .54
Atomic weight u 150 .4 Melting point K 1345
Bonding radius A 1 .62 Boiling point K 2064
Atomic radius A 2 .59 Heat of vaporization kJ/mol 166 .4
Ionization Potential V 5 .64 Heat of fusion kJ/mol 8 .63
Electronegativity - 1 .17 Specific heat J/gK 0 .2
The oxide is mildly basic.
Crystal are rhombohedral.

Electron config. : [Xe] 4f6 6s2


Isotopes of Sm: Click mass number for decay process, product for element page.


131
1.2 sec
EC/ECp,4.300
Pm-131/Nd-130
130.94494
132
4.0 sec
EC/ECp,5.500
Pm-132/Nd-131
131.93991
133
3.7 sec
EC/ECp,7.000
Pm-133/Nd-132
132.93870
134
10 sec
EC,5.400 MeV
Pm-134
133.93397
135
10.3 sec
EC/ECp,7.200
Pm-135/Nd-134
134.93236
136
47 sec
EC,4.500 MeV
Pm-136
135.92828
137
45 sec
EC,6.100 MeV
Pm-137
136.92710
138
3.1 min
EC,3.900 MeV
Pm-138
137.92356
139
2.57 min
EC,5.460 MeV
Pm-139
138.92264
140
14.82 min
EC,3.020 MeV
Pm-140
139.91908
141
10.2 min
EC,4.543 MeV
Pm-141
140.91847
142
72.49 min
EC,2.090 MeV
Pm-142
141.91519
143
8.83 min
EC,3.443 MeV
Pm-143
142.91462
144 3.1%

Stable

143.91199
145
340 da
EC,2.322 MeV
Pm-145
144.91340
146
10.3E+7 yr
a,2.529 MeV
Nd-142
145.91303
147 15.0%
1.06E+11 yr
a,2.310 MeV
Nd-143
146.91489
148 11.3%
7E+15 yr
a,1.986 MeV
Nd-144
147.91481
149 13.8%
2E+15 yr
a,1.071 MeV
Nd-145
148.91718
150 7.4%

Stable

149.91727
151
90 yr
B-,1.187 MeV
Eu-151
150.91992
152 26.7%

Stable

151.91972
153
46.27 hr
B-,1.900 MeV
Eu-153
152.92209
154 22.7%

Stable

153.92220
155
22.3 min
B-,1.627 MeV
Eu-155
154.92463
156
9.4 hr
B-,5.160 MeV
Eu-156
155.92552
157
482 sec
B-,2.730 MeV
Eu-157
156.92835
158
5.30 min
B-,1.999 MeV
Eu-158
157.92998
159
11.37 sec
B-,3.800 MeV
Eu-159
158.93322
160
9.6 sec
B-,3.000 MeV
Eu-160
159.93515
MASS abund.
Halflife
Particle, Energy
Decay Product(s)
Isotopic Mass