c1d6df67_C18s_Are_the_Same_Aren_t_They___2
[0] B [2] 
Hydrogen Bond Basicity. Desirable feature built into certain stationary phases (e.g. polar embedded phases) to provide significantly modified selectivity. Larger ‘B’ values can have considerable effects in enhancing retention of weak acids.
All HPLC C18s Are the Same Aren’t They?
2