xraydb 0.4.0

//! Embedded materials table, ported from upstream XrayDB `materials.dat`.

/// A named material with its chemical formula and nominal density.
#[derive(Debug, Clone, Copy, PartialEq)]
pub struct Material {
    /// Common name, lowercase (e.g. `"kapton"`).
    pub name: &'static str,
    /// Chemical formula, parseable by [`crate::chemparser::chemparse`].
    pub formula: &'static str,
    /// Nominal density in g/cm³.
    pub density: f64,
}

/// Embedded materials database (from XrayDB materials.dat).
///
/// Each entry: (name, density_g_per_cm3, formula)
pub(crate) const MATERIALS: &[(&str, f64, &str)] = &[
    // Gases
    ("hydrogen", 0.0000899, "H"),
    ("helium", 0.0001786, "He"),
    ("nitrogen", 0.00125, "N"),
    ("oxygen", 0.001429, "O"),
    ("neon", 0.0009002, "Ne"),
    ("argon", 0.001784, "Ar"),
    ("krypton", 0.003749, "Kr"),
    ("xenon", 0.005894, "Xe"),
    (
        "air",
        0.001225,
        "(N2)0.7808(O2)0.2095Ar9.34e-3(CO2)4.1e-4Ne1.82e-5He5.24e-6(CH4)1.8e-6Kr1.0e-6(H2)0.5e-6Xe9.e-8",
    ),
    ("methane", 0.000657, "CH4"),
    ("carbon dioxide", 0.001562, "CO2"),
    // Solvents
    ("water", 1.0, "H2O"),
    ("ethanol", 0.789, "C2H5OH"),
    ("acetone", 0.785, "C3H6O"),
    ("methanol", 0.791, "CH3OH"),
    ("isopropanol", 0.803, "C3H8O"),
    ("toluene", 0.867, "C7H8"),
    ("xylene", 0.844, "C6H4(CH3)2"),
    ("benzene", 0.877, "C6H6"),
    ("butanol", 0.810, "C4H10O"),
    ("chlorobenzene", 1.106, "C6H5Cl"),
    ("cyclohexane", 0.774, "C6H12"),
    ("dimethyl sulfoxide", 1.09, "C2H6OS"),
    ("ethylene glycol", 1.115, "C2H6O2"),
    ("glycerin", 1.261, "C3H8O3"),
    ("heptane", 0.684, "C7H16"),
    ("hexane", 0.659, "C6H14"),
    // Polymers
    ("kapton", 1.42, "C22H10N2O5"),
    ("polyimide", 1.42, "C22H10N2O5"),
    ("polypropylene", 0.86, "C3H6"),
    ("pmma", 1.18, "C5H8O2"),
    ("polycarbonate", 1.2, "C16H14O3"),
    ("kimol", 1.2, "C16H14O3"),
    ("mylar", 1.4, "C10H8O4"),
    ("teflon", 2.2, "C2F4"),
    ("parylene-c", 1.29, "C8H7Cl"),
    ("parylene-n", 1.11, "C8H8"),
    ("peek", 1.32, "C19H14O3"),
    // Ceramics & minerals
    ("boron nitride", 2.1, "BN"),
    ("cubic boron nitride", 3.45, "BN"),
    ("silicon nitride", 3.17, "Si3N4"),
    ("yag", 4.56, "Y3Al5O12"),
    ("sapphire", 4.0, "Al2O3"),
    ("ule glass", 2.205, "Si0.925Ti0.075O2"),
    (
        "zerodur",
        2.53,
        "Si0.56Al0.5P0.16Li0.04Ti0.02Zr0.02Zn0.03O2.46",
    ),
    ("fluorite", 3.18, "CaF2"),
    ("mica", 2.83, "KAl3Si3O12H2"),
    ("fayalite", 4.392, "Fe2SiO4"),
    ("forsterite", 3.27, "Mg2SiO4"),
    ("wustite", 5.7, "FeO"),
    ("salt", 2.165, "NaCl"),
    ("silica", 2.2, "SiO2"),
    ("quartz", 2.65, "SiO2"),
    ("cristobalite", 2.27, "SiO2"),
    ("rutile", 4.23, "TiO2"),
    ("magnesium dioxide", 3.6, "MgO"),
    ("galena", 7.60, "PbS"),
    // Semiconductors
    ("cadmium telluride", 5.85, "CdTe"),
    ("gallium arsenide", 5.318, "GaAs"),
    // Metals & elements
    ("beryllium copper", 8.4, "Cu0.98Be0.02"),
    ("diamond carbon", 3.52, "C"),
    ("graphite carbon", 2.23, "C"),
    ("beryllium", 1.85, "Be"),
    ("aluminum", 2.70, "Al"),
    ("silicon", 2.329, "Si"),
    ("titanium", 4.506, "Ti"),
    ("chromium", 7.15, "Cr"),
    ("iron", 7.88, "Fe"),
    ("cobalt", 8.90, "Co"),
    ("nickel", 8.908, "Ni"),
    ("copper", 8.96, "Cu"),
    ("zinc", 7.14, "Zn"),
    ("gallium", 5.91, "Ga"),
    ("germanium", 5.323, "Ge"),
    ("molybdenum", 10.28, "Mo"),
    ("ruthenium", 12.45, "Ru"),
    ("rhodium", 12.41, "Rh"),
    ("palladium", 12.02, "Pd"),
    ("silver", 10.49, "Ag"),
    ("indium", 7.31, "In"),
    ("tin", 7.265, "Sn"),
    ("tantalum", 16.69, "Ta"),
    ("tungsten", 19.25, "W"),
    ("rhenium", 21.02, "Re"),
    ("osmium", 22.59, "Os"),
    ("iridium", 22.56, "Ir"),
    ("platinum", 21.45, "Pt"),
    ("gold", 19.3, "Au"),
    ("mercury", 13.534, "Hg"),
    ("lead", 11.34, "Pb"),
    ("bismuth", 9.78, "Bi"),
    ("uranium", 19.1, "U"),
    ("zirconium", 6.5, "Zr"),
];

/// Find a material by name (case-insensitive) or by exact formula.
pub(crate) fn find_material(name: &str) -> Option<Material> {
    // Name first, so "silica" and "quartz" keep their distinct densities even though
    // both are SiO2.
    for &(mat_name, density, formula) in MATERIALS {
        if mat_name.eq_ignore_ascii_case(name) {
            return Some(Material {
                name: mat_name,
                formula,
                density,
            });
        }
    }
    for &(mat_name, density, formula) in MATERIALS {
        if formula.eq_ignore_ascii_case(name) {
            return Some(Material {
                name: mat_name,
                formula,
                density,
            });
        }
    }
    None
}

/// Every material in the table, in declaration order (gases, solvents, polymers,
/// ceramics, semiconductors, metals).
pub(crate) fn all_materials() -> impl Iterator<Item = Material> {
    MATERIALS.iter().map(|&(name, density, formula)| Material {
        name,
        formula,
        density,
    })
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn lookup_by_name_is_case_insensitive() {
        for query in ["kapton", "Kapton", "KAPTON"] {
            let m = find_material(query).unwrap();
            assert_eq!(m.name, "kapton");
            assert_eq!(m.formula, "C22H10N2O5");
        }
    }

    #[test]
    fn lookup_by_formula_works() {
        let m = find_material("CdTe").unwrap();
        assert_eq!(m.name, "cadmium telluride");
    }

    #[test]
    fn name_lookup_wins_over_formula_lookup() {
        // Both "silica" and "quartz" are SiO2 but have different densities.
        assert_eq!(find_material("quartz").unwrap().density, 2.65);
        assert_eq!(find_material("silica").unwrap().density, 2.2);
    }

    #[test]
    fn material_names_are_unique() {
        let mut names: Vec<&str> = MATERIALS.iter().map(|&(n, _, _)| n).collect();
        names.sort_unstable();
        let before = names.len();
        names.dedup();
        assert_eq!(before, names.len(), "duplicate material name in table");
    }

    #[test]
    fn all_densities_are_positive_and_finite() {
        for m in all_materials() {
            assert!(
                m.density.is_finite() && m.density > 0.0,
                "{} has density {}",
                m.name,
                m.density
            );
        }
    }
}