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                                                                    Exhibit 4.1

                                  $500,000,000
                               EXELON CORPORATION
                               6 3/4% SENIOR NOTES

                               EXELON CORPORATION

                              OFFICER'S CERTIFICATE

              Pursuant to Sections 2.4(3) and 10.5 of the Indenture
                             dated as of May 8, 2001

                  I, J. Barry Mitchell, Vice President of Exelon, a Pennsylvania
Corporation (the "Company"), do hereby certify to Chase Manhattan Trust Company,
National Association, as Trustee (the "Trustee"), under the Indenture dated as
of May 1, 2001 (the "Indenture"), that the terms of the Company's 6 3/4% Senior
Notes due 2011 (the "Notes") to be issued pursuant to the Indenture were
established in or pursuant to resolutions of the Pricing Committee of the Board
of Directors (the "Resolutions"), a copy of which is attached hereto as EXHIBIT
A, and Sections 2.1, 2.3 and 10.5 of the Indenture and complies with the
Indenture as follows:

                  (i)      the Notes are to be entitled "6 3/4% Senior Notes
                           due 2011";

                  (ii)     the Notes initially will be limited in aggregate
                           principal amount to $500,000,000; provided, that the
                           Company may from time to time without notice to, or
                           the consent of, the holders of the Notes, create and
                           issue additional notes of the same series, equal in
                           rank to the Notes in all respects (or in all
                           respects except for the payment of interest accruing
                           prior to the issue date of the new notes or except
                           for the first payment of interest following the
                           issue date of the new notes) so that the new notes
                           may be consolidated and form a single series with
                           the Notes and have the same terms as to status,
                           redemption or otherwise as the Notes;

                  (iii)    the Notes are issued at 100% of the principal amount;

                  (iv)     the maturity date of the Notes is May 1, 2011;

                  (v)      the interest rate for the Notes is 6 3/4% per annum,
                           shall accrue on the Notes commencing May 8, 2001, and
                           that interest on the Notes shall be computed on the
                           basis of a 360-day year composed of twelve 30-day
                           months;

                  (vi)     the interest on the Notes shall be payable
                           semi-annually on May 1 and November 1 in each year
                           commencing November 1, 2001; the regular record dates
                           to determine the holders of the Senior Notes for the
                           purpose of interest payments shall be the April 15 or
                           October 15;
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                  (vii)    the Notes are issued only in registered form in
                           denominations of $1,000 and multiples thereof;

                  (viii)   the Notes are to be issued in book-entry only form
                           with The Depository Trust Company registered in the
                           name of Cede & Co, as nominee for The Depository
                           Trust Company, and so long as in book-entry only form
                           are not issuable in definitive form;

                  (ix)     the Trustee is designated as registrar and transfer
                           agent for the Notes and a Corporate Trust Office to
                           be designated by the Trustee shall be the agency to
                           be maintained by the Company at which books for the
                           registration, exchange and transfer of such Notes
                           shall be kept;

                  (x)      the Notes are not entitled to any sinking funds;

                  (xi)     the Notes are issued as registered securities with
                           the Securities and Exchange Commission;

                  (xii)    the Company will not pay any additional amounts on
                           the Notes held by a person who is not a U.S.
                           citizen in respect of any tax, assessment or
                           governmental charge withheld or deducted;

                  (xiii)   the Notes are redeemable in whole or in part, at any
                           time at the Company's option, at a redemption price
                           equal to the greater of (1) 100% of the principal
                           amount of the Notes being redeemed or (2) the sum of
                           the present values of the remaining scheduled
                           payments of principal and interest thereon
                           (exclusive of interest accrued to the date of
                           redemption) discounted to the redemption date on a
                           semiannual basis (assuming a 360-day year consisting
                           of twelve 30-day months) at the Treasury Rate (as
                           defined below) plus twenty-five (25) basis points,
                           plus accrued interest on the principal amount being
                           redeemed to the redemption date as set forth in the
                           Resolutions and the Prospectus Supplement dated May
                           3, 2001 (the "Prospectus Supplement"), a copy of
                           which is attached hereto as EXHIBIT B:

                                    "Comparable Treasury Issue" means the United
                                    States Treasury security or securities
                                    selected by an Independent Investment Banker
                                    (as defined below) as having an actual or
                                    interpolated maturity comparable to the
                                    remaining term of the notes being redeemed
                                    that would be utilized, at the time of
                                    selection and in accordance with customary
                                    financial practice, in pricing new issues of
                                    corporate debt securities of comparable
                                    maturity to the remaining term of such
                                    Notes.

                                    "Comparable Treasury Price" means, with
                                    respect to any redemption date, (1) the
                                    average of the Reference Treasury Dealer
                                    Quotations (as defined below) for such
                                    redemption date, after


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                                    excluding the highest and lowest such
                                    Reference Treasury Dealer Quotations,
                                    or (2) if the trustee obtains fewer
                                    than four such Reference Treasury
                                    Dealer Quotations, the average of all
                                    such quotations.

                                    "Independent Investment Banker" means one of
                                    the Reference Treasury Dealers (as defined
                                    below) appointed by the trustee after
                                    consultation with the Company.

                                    "Reference Treasury Dealer" means each of
                                    Credit Suisse First Boston Corporation,
                                    Salomon Smith Barney Inc., Banc One Capital
                                    Markets, Inc., their respective successors,
                                    and two other primary U.S. Government
                                    securities dealers in The City of New York
                                    (a "Primary Treasury Dealer") selected by
                                    us. If any Reference Treasury Dealer shall
                                    cease to be a Primary Treasury Dealer, we
                                    will substitute another Primary Treasury
                                    Dealer for that dealer.

                                    "Reference Treasury Dealer Quotations"
                                    means, with respect to each Reference
                                    Treasury Dealer and any redemption date, the
                                    average, as determined by the trustee, of
                                    the bid and asked prices for the Comparable
                                    Treasury Issue (expressed in each case as a
                                    percentage of its principal amount) quoted
                                    in writing to the trustee by such Reference
                                    Treasury Dealer at 3:30 p.m. New York time
                                    on the third business day preceding such
                                    redemption date.

                                    "Treasury Rate" means, with respect to any
                                    redemption date, the rate per annum equal to
                                    the semiannual equivalent yield to maturity
                                    or interpolated (on a day count basis) of
                                    the Comparable Treasury Issue, assuming a
                                    price for the Comparable Treasury Issue
                                    (expressed as a percentage of its principal
                                    amount) equal to the Comparable Treasury
                                    Price for such redemption date;

                  (xiv)    the following are modifications of and additions to
                           the Events of Default and covenants with respect to
                           the Notes, all as described in the Resolutions and
                           the Prospectus Supplement:

                                    Additional Covenants: For so long as any
                                    Notes remain outstanding, the Company will
                                    not create or incur or allow any of its
                                    subsidiaries to create or incur any pledge
                                    or security interest on (1) any of the
                                    capital stock of, or other equity interests
                                    in, PECO Energy Company ("PECO"),
                                    Commonwealth Edison Company ("ComEd") or
                                    Exelon Generation Company, LLC ("Exelon
                                    Generation") and (2) any of the capital
                                    stock of, or other equity interests in, the
                                    Company's subsidiaries which directly hold
                                    the capital stock of or other equity
                                    interests in PECO, ComEd or

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                                    Exelon Generation, in each case held by the
                                    Company or one of its subsidiaries on the
                                    issue date of the Notes.

                                    Additional Events of Default: In addition to
                                    the Events of Default described in the
                                    Indenture, an Event of Default under the
                                    Notes will include the Company's failure to
                                    pay principal at maturity or acceleration
                                    following a default in an aggregate amount
                                    of $50 million or more with respect to any
                                    of the Company's Indebtedness, or the
                                    acceleration of any of the Company's
                                    Indebtedness aggregating $50 million or more
                                    which default is not cured, waived or
                                    postponed pursuant to an agreement with the
                                    holders of the Indebtedness within 30 days
                                    after written notice as provided in the
                                    Indenture, or the acceleration is not
                                    rescinded or annulled within 30 days after
                                    written notice as provided in the Indenture.

                                    As used in the immediately preceding
                                    paragraph, "Indebtedness" means the
                                    following obligations of the Company:

                                    o  all obligations for borrowed money;

                                    o  all obligations evidenced by bonds,
                                       debentures, notes or similar
                                       instruments, or upon which interest
                                       payments are customarily made;

                                    o  all obligations under conditional
                                       sale or other title retention
                                       agreements relating to property
                                       purchased by us to the extent of the
                                       value of the property (other than
                                       customary reservations or retentions
                                       of title under agreements with
                                       suppliers entered into in the
                                       ordinary course of our business);
                                       and

                                    o  all obligations issued or assumed
                                       as the deferred purchase price of
                                       property or services purchased by
                                       us which would appear as liabilities
                                       on our balance sheet; and

                  (xv)     the form of the Notes established pursuant to
                           the Board Resolution is attached hereto
                           as part of EXHIBIT A.

                  In addition, I hereby certify that I have read the Indenture,
including Section 10.5 thereof, and the definitions in such Indenture relating
thereto and certain other corporate documents and records, and having made such
examination or investigation as I consider necessary to enable me to express an
informed opinion and, in my opinion, based on such examination, all conditions
precedent provided for in the Indenture with respect to the authentication,
issuance and delivery of the Certificate representing the 6 3/4% Senior Notes
have been complied with.

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                  All capitalized terms not defined herein shall have the
meanings assigned thereto in the Indenture.

                  IN WITNESS WHEREOF, the undersigned has executed this
certificate this 8th day of May, 2001.

                                             /s/ J. Barry Mitchell
                                             -----------------------------
                                             J. Barry Mitchell
                                             Vice President and Treasurer


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