Cesium Isotopic Data
Isotope |
Isotopic Mass amu |
% Abundance |
T1/2 |
T1/2 Units |
Mass Excess KeV |
Binding Energy Per Nucleon KeV |
Decay Mode |
Branching Ratio |
112Cs | 111.95030 (33) |
| 500 | us | -46,290 (300) | 8,100 (3) | p | 100 |
113Cs | 112.94449 (11) |
| 16.7 | us | -51,700 (100) | 8,148.1 (9.2) | p | 100 |
114Cs | 113.94145 (33) |
| 570 | ms | -54,540 (300) | 8,172 (3) | B+~100 |
|
115Cs | 114.93591 (32) |
| 1.4 | s | -59,700 (300) | 8,216 (3) | B+ | 100 |
116Cs | 115.93337 (11) |
| 700 | ms | -62,070 (100) | 8,235 (1) | B+ | 100 |
117Cs | 116.928671 (67) |
| 8.4 | s | -66,443 (62) | 8,271.4 (5.3) | B+ | 100 |
118Cs | 117.926559 (14) |
| 14 | s | -68,409 (13) | 8,286.4 (1.1) | B+ | 100 |
119Cs | 118.922377 (15) |
| 43 | s | -72,305 (14) | 8,317.3 (1.2) | B+ | 100 |
120Cs | 119.920677 (11) |
| 61.2 | s | -73,889 (10) | 8,328.48 (8.3) | B+ | 100 |
121Cs | 120.917229 (15) |
| 155 | s | -77,100 (14) | 8,352.9 (1.1) | B+ | 100 |
122Cs | 121.916113 (34) |
| 21.18 | s | -78,140 (32) | 8,359.1 (2.6) | B+ | 100 |
123Cs | 122.912996 (13) |
| 5.87 | m | -81,044 (12) | 8,380.38 (9.8) | B+ | 100 |
124Cs | 123.9122578 (89) |
| 30.9 | s | -81,731.3 (8.3) | 8,383.43 (6.7) | B+ | 100 |
125Cs | 124.9097283 (83) |
| 45 | m | -84,087.6 (7.7) | 8,399.79 (6.2) | B+ | 100 |
126Cs | 125.909452 (13) |
| 1.64 | m | -84,345 (12) | 8,399.22 (9.6) | B+ | 100 |
127Cs | 126.9074175 (60) |
| 6.25 | h | -86,240.0 (5.6) | 8,411.56 (4.4) | B+ | 100 |
128Cs | 127.9077489 (59) |
| 3.64 | m | -85,931.4 (5.5) | 8,406.49 (4.3) | B+ | 100 |
129Cs | 128.9060644 (49) |
| 32.06 | h | -87,500.4 (4.6) | 8,416.06 (3.6) | B+ | 100 |
130Cs | 129.9067086 (90) |
| 29.21 | m | -86,900.4 (8.4) | 8,408.79 (6.4) | B+ | 98.4 |
131Cs | 130.9054639 (54) |
| 9.689 | d | -88,059.8 (5) | 8,415.06 (3.8) | EC | |
132Cs | 131.9064343 (20) |
| 6.479 | d | -87,155.9 (1.9) | 8,405.61 (1.4) | B+ | 98.13 9 |
133Cs | 132.905451932 (23) | 100 | stable |
| -88,070.958 (22) | 8,410 (0) |
|
|
134Cs | 133.906718475 (28) |
| 2.0648 | y | -86,891.181 (26) | 8,399 (0) | B- | 100 |
135Cs | 134.9059770 (11) |
| 2.3 | My | -87,581.9 (1) | 8,401.338 (7) | B- | 100 |
136Cs | 135.9073116 (20) |
| 13.16 | d | -86,338.7 (1.9) | 8,389.77 (1.4) | B- | 100 |
137Cs | 136.90708947 (49) |
| 30.1671 | y | -86,545.60 (46) | 8,388.956 (3) | B- | 100 |
138Cs | 137.9110167 (98) |
| 33.41 | m | -82,887.4 (9.2) | 8,360.15 (6.6) | B- | 100 |
139Cs | 138.9133640 (34) |
| 9.27 | m | -80,700.9 (3.2) | 8,342.34 (2.3) | B- | 100 |
140Cs | 139.9172824 (88) |
| 63.7 | s | -77,051.0 (8.2) | 8,314.33 (5.9) | B- | 100 |
141Cs | 140.920046 (11) |
| 24.84 | s | -74,477 (11) | 8,294.35 (7.5) | B- | 100 |
142Cs | 141.924299 (11) |
| 1.689 | s | -70,515 (11) | 8,264.88 (7.5) | B- | 100 |
143Cs | 142.927352 (25) |
| 1.791 | s | -67,671 (24) | 8,243.6 (1.7) | B- | 100 |
144Cs | 143.932077 (28) |
| 994 | ms | -63,270 (26) | 8,211.9 (1.8) | B- | 100 |
145Cs | 144.935526 (12) |
| 582 | ms | -60,057 (11) | 8,188.75 (7.5) | B- | 100 |
146Cs | 145.940289 (77) |
| 323 | ms | -55,620 (71) | 8,157.6 (4.9) | B- | 100 |
147Cs | 146.944155 (57) |
| 225 | ms | -52,019 (53) | 8,132.5 (3.6) | B- | 100 |
148Cs | 147.94922 (62) |
| 146 | ms | -47,300 (580) | 8,100 (3.9) | B- | 100 |
149Cs | 148.95293 (21) |
| 150 | ms | -43,850 (200) | 8,077 (1) | B- ? |
|
150Cs | 149.95817 (32) |
| 100 | ms | -38,960 (300) | 8,044 (2) | B- ? |
|
151Cs | 150.96219 (54) |
| 60 | ms | -35,220 (500) | 8,020 (3) | B- ? |
|
116mCs | 115.93337 (11) |
| 3.85 | s | -62,070 (100) | 8,235 (1) | B+ | 100 |
117mCs | 116.928671 (67) |
| 6.5 | s | -66,443 (62) | 8,271.4 (5.3) | B+ | 100 |
118mCs | 117.926559 (14) |
| 17 | s | -68,409 (13) | 8,286.4 (1.1) | B+ | 100 |
119mCs | 118.922377 (15) |
| 30.4 | s | -72,305 (14) | 8,317.3 (1.2) | B+ | 100 |
120mCs | 119.920677 (11) |
| 57 | s | -73,889 (10) | 8,328.48 (8.3) | B+ | 100 |
121mCs | 120.917229 (15) |
| 122 | s | -77,100 (14) | 8,352.9 (1.1) | B+ | 83 |
122mCs | 121.916113 (34) |
| 3.7 | m | -78,140 (32) | 8,359.1 (2.6) | B+ | 100 |
123mCs | 122.912996 (13) |
| 1.64 | s | -81,044 (12) | 8,380.38 (9.8) | IT | 100 |
124mCs | 123.9122578 (89) |
| 6.3 | s | -81,731.3 (8.3) | 8,383.43 (6.7) | IT | 100 |
125mCs | 124.9097283 (83) |
| 900 | ms | -84,087.6 (7.7) | 8,399.79 (6.2) | IT | 100 |
126mCs | 125.909452 (13) |
| >1 | us | -84,345 (12) | 8,399.22 (9.6) | IT | 100 |
127mCs | 126.9074175 (60) |
| 55 | us | -86,240.0 (5.6) | 8,411.56 (4.4) | IT | 100 |
130mCs | 129.9067086 (90) |
| 3.46 | m | -86,900.4 (8.4) | 8,408.79 (6.4) | IT~100 |
|
134mCs | 133.906718475 (28) |
| 2.903 | h | -86,891.181 (26) | 8,399 (0) | IT | 100 |
135mCs | 134.9059770 (11) |
| 53 | m | -87,581.9 (1) | 8,401.338 (7) | IT | 100 |
136mCs | 135.9073116 (20) |
| 19 | s | -86,338.7 (1.9) | 8,389.77 (1.4) | IT | ? |
138mCs | 137.9110167 (98) |
| 2.91 | m | -82,887.4 (9.2) | 8,360.15 (6.6) | IT | 81 2 |
144mCs | 143.932077 (28) |
| <1 | s | -63,270 (26) | 8,211.9 (1.8) | B- | ? |
122m1Cs | 121.916113 (34) |
| 360 | ms | -78,140 (32) | 8,359.1 (2.6) | IT | 100 |
126m1Cs | 125.909452 (13) |
| 171 | us | -84,345 (12) | 8,399.22 (9.6) | IT | 100 |
117m1Cs | 116.928671 (67) |
| ? |
| -66,443 (62) | 8,271.4 (5.3) | 0 |
|
118m1Cs | 117.926559 (14) |
| R<0.1 |
| -68,409 (13) | 8,286.4 (1.1) | 0 |
|
119m1Cs | 118.922377 (15) |
| R=.5~~.25 |
| -72,305 (14) | 8,317.3 (1.2) | 0 |
|
120m1Cs | 119.920677 (11) |
| R<0.1 |
| -73,889 (10) | 8,328.48 (8.3) | 0 |
|
123m1Cs | 122.912996 (13) |
| R<0.1 |
| -81,044 (12) | 8,380.38 (9.8) | 0 |
|
124m1Cs | 123.9122578 (89) |
| ? |
| -81,731.3 (8.3) | 8,383.43 (6.7) | 0 |
|
130m1Cs | 129.9067086 (90) |
| R=.2~~~.1 |
| -86,900.4 (8.4) | 8,408.79 (6.4) | 0 |
|
138m1Cs | 137.9110167 (98) |
| ? |
| -82,887.4 (9.2) | 8,360.15 (6.6) | 0 |
|
Data Source: ENSDF March 2005
©Radiochemistry Society 2005