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The configuration calculator determines the electronic structure of atoms by distributing electrons across orbitals according to the Aufbau filling order.

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How it works

The calculator uses the getElementData() function to compute electron configurations based on atomic number (Z). It fills orbitals sequentially following the energy-level hierarchy:
chemistry.js
const sequence = [
  { n: "1s", max: 2 }, { n: "2s", max: 2 }, { n: "2p", max: 6 },
  { n: "3s", max: 2 }, { n: "3p", max: 6 }, { n: "4s", max: 2 },
  { n: "3d", max: 10 }, { n: "4p", max: 6 }, { n: "5s", max: 2 },
  { n: "4d", max: 10 }, { n: "5p", max: 6 }, { n: "6s", max: 2 },
  { n: "4f", max: 14 }, { n: "5d", max: 10 }, { n: "6p", max: 6 },
  { n: "7s", max: 2 }, { n: "5f", max: 14 }, { n: "6d", max: 10 },
  { n: "7p", max: 6 }
];

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Orbital filling logic

The algorithm processes each orbital subshell in the sequence defined above:
  1. Determines how many electrons to place in the current orbital (minimum of remaining electrons and orbital capacity)
  2. Adds the orbital and electron count to the configuration array
  3. Tracks the highest principal quantum number to identify valence electrons
  4. Continues until all electrons are distributed
chemistry.js
for (let sub of sequence) {
  if (remaining <= 0) break;
  let count = Math.min(remaining, sub.max);
  config.push({ label: sub.n, electrons: count });
  
  let currentLevel = parseInt(sub.n[0]);
  if (currentLevel > lastLevel) {
    lastLevel = currentLevel;
    valenceElectrons = count;
  } else if (currentLevel === lastLevel) {
    valenceElectrons += count;
  }
  remaining -= count;
}

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Return values

The getElementData() function returns an object containing:
  • z — Atomic number
  • configString — Full electron configuration (e.g., “1s2 2s2 2p6 3s2 3p2”)
  • valenceElectrons — Number of electrons in the outermost shell
  • holes — Number of holes calculated as 8 - valenceElectrons

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Example outputs

{
  z: 14,
  configString: "1s2 2s2 2p6 3s2 3p2",
  valenceElectrons: 4,
  holes: 4
}

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Valence electron calculation

Valence electrons are identified by tracking the highest principal quantum number (n) encountered during filling:
  • When a new shell is encountered (higher n), the valence count resets to the electrons in that shell
  • Electrons added to the same shell level accumulate in the valence count
  • This approach correctly handles transition metals where d-orbitals fill after the next s-orbital
The valence electron count is critical for determining semiconductor behavior. Elements with 3, 4, or 5 valence electrons form the basis of P-type, intrinsic, and N-type semiconductors respectively.

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Material type determination

The determineMaterial() function uses valence electron counts to classify semiconductor combinations:
chemistry.js
if (v1 === 4 && v2 === 4) return "Intrínseco (Aislante)";
if ((v1 === 4 && v2 === 5) || (v1 === 5 && v2 === 4)) return "Tipo N (Exceso de electrones)";
if ((v1 === 4 && v2 === 3) || (v1 === 3 && v2 === 4)) return "Tipo P (Exceso de huecos)";
This logic determines whether doping creates an N-type (electron donor) or P-type (hole donor) semiconductor.

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