{
  "chain": "Standard-model particles & forces  --[Strong force binds quarks->nucleons; nucleon count sets Z, isotope, nuclear charge.]-->  Nucleus, electrons, isotopes (evidence=review, uncertainty=low)\nNucleus, electrons, isotopes  --[Nuclear charge Z + relativistic contraction of inner s-orbitals fix electron configuration and effective nuclear charge.]-->  Element & electron configuration (evidence=review, uncertainty=low)\nElement & electron configuration  --[Electron configuration determines valence electrons, orbital energies, electronegativity, ionization energy.]-->  Orbitals & valence electrons (evidence=review, uncertainty=low)\nOrbitals & valence electrons  --[Electronegativity difference + orbital overlap select bond type (ionic/covalent/metallic/H-bond/vdW/coordinate/pi).]-->  Bonding type (evidence=review, uncertainty=low)\nBonding type  --[Bond directionality + packing determine crystal structure, coordination, and stable phase.]-->  Molecule / lattice / phase (evidence=review, uncertainty=low)\nMolecule / lattice / phase  --[Periodic potential -> band structure; overlap/gap sets metal vs semiconductor vs insulator, plasma frequency, Fermi level.]-->  Bands, band gap, carriers (evidence=review, uncertainty=low)\nMolecule / lattice / phase  --[Composition + processing introduce dopants, vacancies, oxidation states, ligand-field environments.]-->  Defects, doping, oxidation state, ligand field (evidence=review, uncertainty=medium)\nDefects, doping, oxidation state, ligand field  --[d-d transitions, charge-transfer, color centers, and dopant levels add discrete absorption bands in the visible.]-->  Absorption / reflection / scattering / interference (evidence=review, uncertainty=medium)\nBands, band gap, carriers  --[Band gap sets absorption edge; free carriers set reflectance/plasma edge (metallic luster) via n, k.]-->  Absorption / reflection / scattering / interference (evidence=review, uncertainty=low)\nGrains, pores, interfaces, surface roughness  --[Grain/pore/roughness scale vs wavelength controls specular-vs-diffuse reflection, scattering, and thin-film interference.]-->  Absorption / reflection / scattering / interference (evidence=review, uncertainty=medium)\nMolecule / lattice / phase  --[Processing (anneal, deposition, polishing) sets grain size, porosity, roughness, oxide film, coatings.]-->  Grains, pores, interfaces, surface roughness (evidence=review, uncertainty=medium)\nAbsorption / reflection / scattering / interference  --[Absorption spectrum -> perceived colour; reflectance + surface order -> luster; roughness/modulus/friction -> texture.]-->  Colour / luster / texture / hardness / conductivity (evidence=review, uncertainty=medium)"
}