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One of the most important factors in determining the stellar lithiumabundance is the effective temperature. In a previous study by the authors, neweffective temperatures Teff for sixteen metal-poor halo dwarfs were derivedusing a local thermodynamic equilibrium (LTE) description of the formation ofFe lines. This new Teff scale reinforced the discrepancy. For six of the starsfrom our previous study we calculate revised temperatures using a non-localthermodynamic equilibrium (NLTE) approach. These are then used to derive a newmean primordial lithium abundance in an attempt to solve the lithiumdiscrepancy. Using the code MULTI we calculate NLTE corrections to the LTEabundances for the Fe I lines measured in the six stars, and determine newTeff's. We keep other physical parameters, i.e. log g, [Fe/H] and xi, constantat the values calculated in Paper I. With the revised Teff scale we derive newLi abundances. We compare the NLTE values of Teff with the photometrictemperatures of Ryan et al. (1999, ApJ, 523, 654), the infrared flux method(IRFM) temperatures of Melendez & Ramirez (2004, ApJ, 615, 33), and the Balmerline wing temperatures of Asplund et al. (2006, ApJ, 644, 229). We find thatour temperatures are hotter than both the Ryan et al. and Asplund et al.temperatures by typically ~ 110 K - 160 K, but are still cooler than thetemperatures of Melendez & Ramirez by typically ~ 190 K. The temperatures implya primordial Li abundance of 2.19 dex or 2.21 dex, depending on the magnitudeof collisions with hydrogen in the calculations, still well below the value of2.72 dex inferred from WMAP + BBN. We discuss the effects of collisions ontrends of 7Li abundances with [Fe/H] and Teff, as well as the NLTE effects onthe determination of log g through ionization equilibrium, which imply acollisional scaling factor SH > 1 for collisions between Fe and H atoms.

Lithium abundances of halo dwarfs based on excitation temperatures. II. NLTE