June 18, 1982

''I NEVER saw her or heard her. Yet I continually bless the name of Ida Rubinstein for, because of her, I've had a whole second career,'' Vera Zorina said the other day during a break between rehearsals for her part in the Stravinsky Centennial Celebration at the New York State Theater. A glamorous star of ballet, Broadway and Hollywood during the 1930's and 40's - when she was married to the choreographer George Balanchine - Miss Zorina has more recently enjoyed success as a reciter in works that combine declamation with music. Tonight, she stars with the New York City Ballet in one of the most famous of all such works, Igor Stravinsky's ''Persephone,'' to a text by Andre Gide.

A Justice Department internal investigation has concluded there was no conflict of interest involved when William F. Baxter, the Assistant Attorney General in charge of the antitrust division, dismissed the Government's suit against the International Business Machines Corporation, a department official said yesterday. J. Paul McGrath, an Assistant Attorney General, disclosed the findings of the investigation to an appeals court in New York. He told the three-judge panel that the Justice Department considers the dismissal final and does not plan to reopen it. ''The findings do not raise any questions about the propriety of the dismissal,'' Mr. McGrath said. ''There was no conflict of interest which barred him from doing that,'' he added, referring to Mr. Baxter.

In a $5.1 billion deal that would be one of the biggest corporate acquisitions on record, the Gulf Oil Corporation said yesterday that it planned to buy the Cities Service Company. The agreement, announced jointly by the two oil giants, was viewed on Wall Street as an effort to frustrate a takeover of Cities Service being attempted by the much smaller Mesa Petroleum Company of Amarillo, Tex. Cities Service has opposed the Mesa attempt. A Gulf-Cities Service combination would be exceeded in value only by the $7.2 billion purchase of Conoco Inc. by A sharp rise in interest rates depressed the prices of stocks and gold. Details in Business Day E.I. du Pont de Nemours & Company last summer and the United States Steel Corporation's $6 billion acquisition of the Marathon Oil Company this year.

Gulf Oil has agreed to take over Cities Service in a $5.1 billion deal that would be one of the biggest acquisitions ever. The move was seen on Wall Street as an effort to frustrate an unwanted takeover of Cities Service being pressed by Mesa Petroleum. A Gulf-Cities Service merger would be exceeded in size only by the purchases of Conoco by Du Pont and Marathon Oil by U.S. Steel, and would create the nation's seventh-largest industrial corporation. (Page A1.) Itel's chairman and chief executive quit the troubled company, citing ''philosophical differences'' with major creditors. The company, which is operating under court protection from its creditors, also filed a reorganization plan in Federal Bankruptcy Court. (D1.)

The City Council and the Board of Estimate, racing to beat a midnight deadline, formally adopted New York City's next budget last night. The process that started months ago culminated at 11:50 A.M., when the City Council voted 37 to 5, with one abstention, to approve a $15.54 billion expense The New Jersey State Assembly approved a 5 percent gasoline surtax, and Governor Kean signed a bill raising the state cigarette tax. Page B2. budget for the fiscal year that begins July 1. The vote followed a marathon negotating session that started Wednesday morning and produced a package of changes valued at $48.2 million in the budget that Mayor Koch had submitted on May 10.