Shunyaya Symbolic Mathematical Chemistry – Contrast-to-Alignment Assignment (3.2)

What this page defines.
How a single energetic contrast is mapped, symmetrically and bounded, to reactant and product alignments. The map is collapse-safe, sign-consistent with the contrast, and uses a global slope so the study remains auditable. Exactly one lens is chosen per study and kept fixed.

Practical notes

  • Default lens (formation/bonds): build contrast from bonds formed vs. broken, then map with a single slope c to reactant/product alignments.
  • Sign convention: use E_formed - E_broken so forward-favored formation yields e > 0.
  • Scales: choose E_unit so |e| is O(1) (e.g., 100 kJ/mol); publish E_unit and c.
  • Bounds: clamp each alignment to the open interval using the study’s eps_a.
  • Direction vs. magnitude: only sign(e) sets direction (see Sign Lemma); magnitudes of a and RSI depend on E_unit and c.
  • Data sources: if bond energies come from tables or estimates, cite source and version in the manifest.
  • Alternatives: other lenses are allowed (thermo/redox/kinetic etc.); pick exactly one per study and publish it.

Plain ASCII formulas (copy-ready)

Default bond/formation lens

E_broken = sum_over_bonds_broken(B_bond)
E_formed = sum_over_bonds_formed(B_bond)
e = ( E_formed - E_broken ) / E_unit    # E_unit > 0

a_react = tanh( -c * e )                 # c > 0
a_prod  = tanh( +c * e )

# clamp to keep |a| <= 1 - eps_a
a_react = clamp_a( a_react , eps_a )
a_prod  = clamp_a( a_prod  , eps_a )

Scope and guards

# One lens per study; keep fixed. Alternatives listed in 4.1.
# Sign convention: E_formed - E_broken -> forward-favored => e > 0
# Scales: choose E_unit so |e| ~ O(1); c is the global slope
# Clamp policy: enforce |a| <= 1 - eps_a after mapping
# Direction vs magnitude: only sign(e) controls sign(RSI); magnitudes depend on E_unit and c
# Data sources: record bond tables/estimates (name, version) in the manifest
# Publish: E_unit, c, eps_a, lens name, and data sources


Navigation
Previous – RSI Overview & Definition (3, 3.1)
Next – Sign Lemma & Monotonicity (3.3, 3.4)