¹²⁶Pm — Unstable · t½ ≈ 5 s · Decay: β⁺ → ¹²⁶Nd · Type: synthetic · Uses: research.
¹²⁷Pm — Unstable · t½ ≈ 2.5 s · Decay: β⁺ → ¹²⁷Nd · Type: synthetic · Uses: research.
¹²⁸Pm — Unstable · t½ ≈ 5.0 s · Decay: β⁺ → ¹²⁸Nd · Type: synthetic · Uses: research.
¹²⁹Pm — Unstable · t½ ≈ 2.0 s · Decay: β⁺ → ¹²⁹Nd · Type: synthetic · Uses: research.
¹³⁰Pm — Unstable · t½ ≈ 6.0 s · Decay: β⁺ → ¹³⁰Nd · Type: synthetic · Uses: research.
¹³¹Pm — Unstable · t½ ≈ 9.0 s · Decay: β⁺ → ¹³¹Nd · Type: synthetic · Uses: research.
¹³²Pm — Unstable · t½ ≈ 7.5 s · Decay: β⁺ → ¹³²Nd · Type: synthetic · Uses: research.
¹³³Pm — Unstable · t½ ≈ 12.0 s · Decay: β⁺ → ¹³³Nd · Type: synthetic · Uses: research.
¹³⁴Pm — Unstable · t½ ≈ 40.0 s · Decay: β⁺ → ¹³⁴Nd · Type: synthetic · Uses: research.
¹³⁵Pm — Unstable · t½ ≈ 3.0 min · Decay: β⁺ → ¹³⁵Nd · Type: synthetic · Uses: research.
¹³⁶Pm — Unstable · t½ ≈ 5.0 min · Decay: β⁺ → ¹³⁶Nd · Type: synthetic · Uses: research.
¹³⁷Pm — Unstable · t½ ≈ 2.6 min · Decay: β⁺ → ¹³⁷Nd · Type: synthetic · Uses: research.
¹³⁸Pm — Unstable · t½ ≈ 10.0 min · Decay: β⁺ → ¹³⁸Nd · Type: synthetic · Uses: research.
¹³⁹Pm — Unstable · t½ ≈ 4.2 min · Decay: β⁺ → ¹³⁹Nd · Type: synthetic · Uses: research.
¹⁴⁰Pm — Unstable · t½ ≈ 5.9 min · Decay: β⁺ → ¹⁴⁰Nd · Type: synthetic · Uses: research.
¹⁴¹Pm — Unstable · t½ ≈ 20.9 min · Decay: β⁻ → ¹⁴¹Sm · Type: synthetic · Uses: research.
¹⁴²Pm — Unstable · t½ ≈ 40.5 s · Decay: β⁺/β⁻ → ¹⁴²Nd/¹⁴²Sm · Type: synthetic · Uses: research.
¹⁴³Pm — Unstable · t½ ≈ 265 d · Decay: β⁻ → ¹⁴³Sm · Type: synthetic · Uses: tracer.
¹⁴⁴Pm — Unstable · t½ ≈ 363 d · Decay: β⁻ → ¹⁴⁴Sm · Type: synthetic · Uses: tracer.
¹⁴⁵Pm — Unstable · t½ ≈ 17.7 y · Decay: β⁻ → ¹⁴⁵Sm · Type: synthetic · Uses: tracer, reactor product.
¹⁴⁶Pm — Unstable · t½ ≈ 5.5 y · Decay: β⁻ → ¹⁴⁶Sm · Type: synthetic · Uses: tracer.
¹⁴⁷Pm — Unstable · t½ ≈ 2.62 y · Decay: β⁻ → ¹⁴⁷Sm · Type: synthetic · Uses: tracer.
¹⁴⁸Pm — Unstable · t½ ≈ 5.4 d · Decay: β⁻ → ¹⁴⁸Sm · Type: synthetic · Uses: tracer.
¹⁴⁹Pm — Unstable · t½ ≈ 53 h · Decay: β⁻ → ¹⁴⁹Sm · Type: synthetic · Uses: tracer.
¹⁵⁰Pm — Unstable · t½ ≈ 2.7 h · Decay: β⁻ → ¹⁵⁰Sm · Type: synthetic · Uses: research.
¹⁵¹Pm — Unstable · t½ ≈ 28 h · Decay: β⁻ → ¹⁵¹Sm · Type: synthetic · Uses: research.
¹⁵²Pm — Unstable · t½ ≈ 4.1 min · Decay: β⁻ → ¹⁵²Sm · Type: synthetic · Uses: research.
¹⁵³Pm — Unstable · t½ ≈ 5.3 min · Decay: β⁻ → ¹⁵³Sm · Type: synthetic · Uses: research.
¹⁵⁴Pm — Unstable · t½ ≈ 2.4 min · Decay: β⁻ → ¹⁵⁴Sm · Type: synthetic · Uses: research.
¹⁵⁵Pm — Unstable · t½ ≈ 1.5 min · Decay: β⁻ → ¹⁵⁵Sm · Type: synthetic · Uses: research.
¹⁵⁶Pm — Unstable · t½ ≈ 25.0 s · Decay: β⁻ → ¹⁵⁶Sm · Type: synthetic · Uses: research.
¹⁵⁷Pm — Unstable · t½ ≈ 10.0 s · Decay: β⁻ → ¹⁵⁷Sm · Type: synthetic · Uses: research.
¹⁵⁸Pm — Unstable · t½ ≈ 5.0 s · Decay: β⁻ → ¹⁵⁸Sm · Type: synthetic · Uses: research.
¹⁵⁹Pm — Unstable · t½ ≈ 3.0 s · Decay: β⁻ → ¹⁵⁹Sm · Type: synthetic · Uses: research.
¹⁶⁰Pm — Unstable · t½ ≈ 2.0 s · Decay: β⁻ → ¹⁶⁰Sm · Type: synthetic · Uses: research.
¹⁶¹Pm — Unstable · t½ ≈ 1.2 s · Decay: β⁻ → ¹⁶¹Sm · Type: synthetic · Uses: research.
¹⁶²Pm — Unstable · t½ ≈ 0.8 s · Decay: β⁻ → ¹⁶²Sm · Type: synthetic · Uses: research.
¹⁶³Pm — Unstable · t½ ≈ 0.6 s · Decay: β⁻ → ¹⁶³Sm · Type: synthetic · Uses: research.
¹⁶⁴Pm — Unstable · t½ ≈ 0.4 s · Decay: β⁻ → ¹⁶⁴Sm · Type: synthetic · Uses: research.
¹⁶⁵Pm — Unstable · t½ ≈ 0.2 s · Decay: β⁻ → ¹⁶⁵Sm · Type: synthetic · Uses: research.
Promethium — isotope count: 40 total · Stable: 0 · Unstable: 40 (all radioactive).
(Data: IAEA LiveChart, NUBASE2020, ENSDF; notable applications: ¹⁴⁷Pm in nuclear batteries, luminous paints, thickness gauges; other isotopes used in tracing and reactor studies. Promethium is the only lanthanide with no stable isotopes.)
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