91 electrons sit in their real ground-state shells (K 2 · L 8 · M 18 · N 32 · O 20 · P 9 · Q 2 · 8 0 · 9 0 · 10 0). Each orbits and jitters as an agent. Heat or a tap lifts one into a higher shell (up to shell 10); it relaxes back and emits a photon.
Tap near an electron to excite it. The same ?seed= always gives the same run.
LITZ = 91, Pa, Protactinium. Standard atomic weight 231.036. Group — (actinide), period 7, f-block.
LITGround-state configuration 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 5f2 6d1 7s2 (NIST). Shells: K 2 · L 8 · M 18 · N 32 · O 20 · P 9 · Q 2 · 8 0 · 9 0 · 10 0. This is an exception to the Madelung (aufbau) filling order, which would give 6p6 7s2 5f3 at the end.
LITFirst ionization energy 5.8900 eV (NIST).
LITIsotopes: 231Pa 100% (natural abundance).
LITEmission lines used for photons: 398.223 nm, 694.572 nm, the strongest neutral-atom (I) lines, air wavelengths, verified against the NIST Handbook of Basic Atomic Spectroscopic Data strong-lines table: https://physics.nist.gov/PhysRefData/Handbook/Tables/protactiniumtable2.htm. Photons are not tied to a specific shell jump (ANALOGY).
WALLShells 8, 9 and 10 are MODEL, Dave’s 10-shell frame: no ground-state atom uses more than 7 shells, so they stay empty unless an electron is excited into them.
AMBERThe orbiting dots are a cartoon (ANALOGY), not orbitals; electron colour is by home shell (q.d), and the nucleus colour is by block (s, p, d, f). The self-check confirms the electron total equals Z, the shell counts sum to Z, every shell is within 2n², and shells 8 to 10 are empty in the ground state; any failure throws.