Measurement of thermionic electron emission values for pointed single-crystal emitter cathodes had shown that <110> axial orientations yielded emission values that were ten times higher than <100> orientations at 1545K. Minimum values were obtained for <510> directions.

Anisotropy of Thermionic Electron Emission Values for LaB6 Single-Crystal Emitter Cathodes. Schmidt, P.H., Joy, D.C., Longinotti, L.D., Leamy, H.J., Ferris, S.D., Fisk, Z.: Applied Physics Letters, 1976, 29[7], 400-1