(** Data structure for Atomic Orbitals. *)

open Qcaml_common
open Qcaml_particles
open Qcaml_operators
open Qcaml_linear_algebra

type basis =
  | Unknown
  | Gaussian of Ao_basis_gaussian.t

type t 

(** {1 Accessors} *)

val size : t -> int
(** Number of atomic orbitals in the AO basis set *)
  
val ao_basis : t -> basis
(** One-electron basis set *)

val overlap : t -> ('a,'a) Matrix.t
(** Overlap matrix *)

val multipole : t -> ('a,'a) Matrix.t array
(** Multipole matrices *)

val ortho : t -> ('a,'a) Matrix.t
(** Orthonormalization matrix of the overlap *)

val eN_ints : t -> ('a,'a) Matrix.t
(** Electron-nucleus potential integrals *)

val kin_ints : t -> ('a,'a) Matrix.t
(** Kinetic energy integrals *)

val ee_ints : t -> 'a Four_idx_storage.t
(** Electron-electron potential integrals *)

val ee_lr_ints : t -> 'a Four_idx_storage.t
(** Electron-electron long-range potential integrals *)

val f12_ints : t -> 'a Four_idx_storage.t
(** Electron-electron potential integrals *)

val f12_over_r12_ints : t -> 'a Four_idx_storage.t
(** Electron-electron potential integrals *)

val cartesian : t -> bool
(** If true, use cartesian Gaussians (6d, 10f, ...) *)

val values : t -> Coordinate.t -> 'a Vector.t
(** Values of the AOs evaluated at a given point *)



(** {1 Creators} *)

val of_nuclei_and_basis_filename :
  ?kind:[> `Gaussian ] -> ?operators:Operator.t list -> ?cartesian:bool ->
  nuclei:Nuclei.t -> string -> t
(** Creates the data structure for atomic orbitals from a {Basis.t} and the
    molecular geometry {Nuclei.t} *)