Protactinium

Energy levels of neutral Protactinium - ²³¹Pa I

• Introduction
• References
• Protactinium I even
• Protactinium I odd

Energy levels of singly-ionized Protactinium - ²³¹Pa II

• Introduction
• References
• Protactinium II even
• Protactinium II odd

Energy levels of trebly-ionized Protactinium - ²³¹Pa IV

• Introduction
• References
• Protactinium IV

Energy levels of sixty-four times ionized Protactinium - Pa LXV

• Introduction
• References
• Protactinium LXV