A former vice president of the Chase Manhattan Bank charges in a $2.5 million lawsuit that another former vice president who was her superior intimidated her into having a sexual affair.

Carolee Koster, 31, says in a suit filed in U.S. District Court against Chase and the former vice president that she suffered discrimination and that to maintain her position was forced to "capitulate" to the sexual demands of Allen Ross, who has since left the company.

A spokesman for Chase, the nation's third largest bank, said the bank had not seen the complaint and "won't have any official comment" until executives review it.

Reached at his home Wednesday night, Ross said the allegations were "absolutely unfounded," and called the sexual harassment charges "pure fabrication."

Koster alleged that Ross kept her salary artificially low and had threatened to ruin her career by giving unfavorable references.

Before she was promoted to vice president, Koster said, Ross said her success depended on him, and he "began demanding sexual favors."

She said that after her mother persuaded her to break off the four-month affair in June, 1979, Ross began to "abuse" her by screaming at her in public, "making fun of me and putting me down in front of anybody who happened to be around."