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Solid-Phase Thermodynamics

A four-tier lookup for solid Cp/enthalpy/entropy: NIST-JANAF Shomate polynomials (temperature-dependent, for NaCl/KCl/quartz), CRC Handbook point values, the Lastovka similarity-variable correlation, then Dulong-Petit as the documented last resort — never raises.

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Concept

Solid-phase Cp/enthalpy/entropy (needed by every solids-train unit op) comes from a four-tier lookup, most-rigorous first: a real temperature-dependent regression when one exists, a curated point value otherwise, a general correlation as a broader fallback, and a documented physical-limit constant so the chain never has no answer.

The math
Show the governing equations
Cp∘(t)=A+Bt+Ct2+Dt3+Et2,t=T/1000 (NIST-JANAF Shomate)C_p^\circ(t) = A + Bt + Ct^2 + Dt^3 + \frac{E}{t^2}, \quad t = T/1000\ \text{(NIST-JANAF Shomate)}
H∘(T)−H298.15∘=At+B2t2+C3t3+D4t4−Et+F−HH^\circ(T)-H^\circ_{298.15} = At+\tfrac{B}{2}t^2+\tfrac{C}{3}t^3+\tfrac{D}{4}t^4-\tfrac{E}{t}+F-H
Cp,∞→3nR(Dulong-Petit high-T limit, the last-resort fallback)C_{p,\infty} \to 3nR \quad \text{(Dulong-Petit high-T limit, the last-resort fallback)}
Execution

Tiers

  1. NIST-JANAF Shomate — real T-dependence, when a caller passes a temperature (NaCl, KCl, quartz).
  2. CRC Handbook Cp°(298.15 K) — curated point values for the rest of the crystallizer solute salts + water-ice.
  3. Lastovka similarity-variable correlation, via the chemicals package.
  4. Dulong-Petit, then a documented flat constant.