exception ElementError of string

type t =
|X
|H                                                 |He
|Li|Be                              |B |C |N |O |F |Ne
|Na|Mg                              |Al|Si|P |S |Cl|Ar
|K |Ca|Sc|Ti|V |Cr|Mn|Fe|Co|Ni|Cu|Zn|Ga|Ge|As|Se|Br|Kr
|Rb|Sr|Y |Zr|Nb|Mo|Tc|Ru|Rh|Pd|Ag|Cd|In|Sn|Sb|Te|I |Xe
                           |Pt          


(** String conversion functions *)
val of_string : string -> t
val to_string : t -> string
val to_long_string : t -> string

(** Properties *)
val to_int : t -> int 
val of_int : int -> t
val to_charge : t -> Charge.t
val of_charge : Charge.t -> t
val covalent_radius : t -> NonNegativeFloat.t
val vdw_radius : t -> NonNegativeFloat.t
val mass : t -> Mass.t