Scale	Value	Source	Method
pauling	1.250	Database	The original and most widely used scale, based on bond dissociation energies. Fl...
allen	N/A	Database	Based on the average energy of valence electrons in free atoms. Provides configu...
ghosh	0.217	Database	Theoretical scale based on absolute electronegativity using DFT calculations.
mulliken χ = (IE + EA) / 6.30	1.145	Calculated	Average of ionization energy and electron affinity, normalized to Pauling scale.
allred rochow χ = 0.359 × (Z_eff / r²) + 0.744	1.908	Calculated	Based on effective nuclear charge and covalent radius. Relates to electrostatic ...
sanderson χ = 0.31 × (electron density)^(1/3)	0.451	Calculated	Based on electron density of atoms. Uses concept of stability ratio for equaliza...
gordy χ = 0.31 × (Z_eff / r) + 0.50	2.409	Calculated	Linear relationship between electronegativity, effective charge, and radius.
cottrell sutton χ = 0.35 × (Z_eff / r) + 0.60	2.755	Calculated	Similar to Gordy scale with adjusted empirical constants for better correlation.
nagle χ = (Z_eff^1.5) / (5r)	4.213	Calculated	Density functional approximation emphasizing the role of effective nuclear charg...
martynov batsanov χ = 0.47 × (Z_eff / r) + 0.62	3.514	Calculated	Refinement of charge-to-distance ratio approach with optimized empirical paramet...
li xue χ = (IE₁ + IE₂ + ... + IEₙ) / (5.5n)	2.541	Calculated	Quantum mechanical approach using average of multiple ionization energies of val...