alists and packages question

Hi,

I am trying to access elements of an alist from a "derived" package.
And I am succeeding, but in an ugly way.  What is the better way?
Here are the details.

I am defining an alist in one package, and I have a function to
retrieve its value.  I have ex****ted that function.

(defpackage :atomic-processes
  (:use :cl :my-utils :physics-constants)
  (:ex****t
....
   :rel-polarizability
   :polarizability))

(in-package :atomic-processes)
(defparameter *alpha-r*
  (list
   (cons 'H 4.5)
   (cons 'C 12.)
....
   (cons 'S-F6 30.))
  "Relative polarizabilities")

(defun rel-polarizability (id)
  (let ((res (cdr (assoc id
			 *alpha-r*))))
    (if (not res)
	(error "not found"))
	res)))

Now, I operate inside another package that uses :atomic-processes
Doing (rel-polarizability 'H) will return the error.  Instead I have
to do (rel-polarizability 'atomic-processes::h).

Is there some way around that?

I tried to build a new symbol as follows:
;; (defun rel-polarizability (id)
;;   (let* ((full-id (make-symbol
;; 		  (concatenate 'string
;; 			       "ATOMIC-PROCESSES::"
;; 			       (symbol-name id))))
;; 	 (res (cdr (assoc full-id
;; 			 *alpha-r*))))
;;     (if (not res)
;; 	(error (concatenate 'string (symbol-name full-id) " not found"))
;; 	res)))

but while it did build the symbol, it did not manage to return the
value.  Puzzled...

Thank you,

Mirko