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IndisputableMonolith.Chemistry.IonicBond

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The IonicBond module defines Recognition Science predicates and energy proxies for ionic bonding, centered on alkali-halogen pairs that combine low ionization energy with high electron affinity. Researchers building parameter-free bond-type classifiers in the φ-ladder framework would cite these definitions. The module consists of element-class predicates, an electronegativity-difference threshold, and lattice-energy proxies assembled from upstream scaling results.

claimLet $Z$ range over atomic numbers. Define alkaliMetalZ and halogenZ as the sets {3,11,19,37,55,87} and {9,17,35,53,85} respectively. Then isIonicBond$(Z_1,Z_2)$ holds when one element belongs to alkaliMetalZ, the other to halogenZ, and the electronegativity difference exceeds ionicThreshold, with latticeEnergyProxy$(Z_1,Z_2)$ given by the Madelung sum for the corresponding crystal structure.

background

The module sits inside the Recognition Science chemistry layer that maps the eight-tick octave of PeriodicTable onto element blocks. Upstream IonizationEnergy supplies the sawtooth I₁(Z) pattern forced by φ-rail scaling φ^{2n} plus position-to-closure factors. ElectronAffinity predicts high values for halogens (one electron short of closure) and low values for alkali metals (one past closure). Electronegativity combines these via the classical √(IE × EA) form modulated by distance to next closure, exactly as stated in its doc-comment.

proof idea

This is a definition module, no proofs. It imports the five upstream modules, declares the concrete Z-sets alkaliMetalZ and halogenZ, lifts the isAlkaliMetal and isHalogen predicates, computes electronegativityDifference from the imported EN function, introduces the fixed ionicThreshold, and assembles isIonicBond together with the three Madelung lattice proxies.

why it matters in Recognition Science

The module supplies the ionic-bond classification that feeds lattice-energy calculations (madelungNaCl, madelungCsCl, madelungZnS) and closes the CH-00x chemistry series. It directly implements the low-ionization-energy property of alkali metals stated in the module doc-comment and connects to the eight-tick octave (T7) and φ-ladder scaling (T6) of the UnifiedForcingChain. It touches the open question of deriving bond-type thresholds without empirical fitting.

scope and limits

depends on (5)

Lean names referenced from this declaration's body.

declarations in this module (19)