code: private String getBetaAromaticType(String symb, boolean imidazolium, boolean anion) {
          return getAromaticType(betaTypes, 'B', symb, imidazolium, anion);
      }
docs: Convenience method to obtain the aromatic type of a symbolic (SYMB) type in the beta position
  of a 5-member ring. This method delegates to {@link #getAromaticType(java.util.Map, char,
  String, boolean, boolean)} setup for beta atoms.
  
  @param symb        symbolic atom type
  @param imidazolium imidazolium flag (IM naming from MMFFAROM.PAR)
  @param anion       anion flag (AN naming from MMFFAROM.PAR)
  @return the aromatic type