The antinuclear movement is likely to get its largest financial boost this week from a series of concerts organized by musicians and "no nukes" activists.

A week of rock-and-roll benefit concerts will be capped Sunday with a rally in Lower Manhattan. Its organizers say the rally will be bigger than the May 6 demonstration in Washington that drew about 100,000 people.

Ralph Nader, Jane Fonda, Tom Hayden, Bella Abzug, Harvard biologist George Wald and Gray Panther leader Maggie Kuhn will be among the speakers at the free five-hour rally, which also will feature music by folk and rock-and-roll artists.

Barry Commoner, a leader of antinuclear proponents, and a representative of the Union of Concerned Scientists will hold a news conference during the week to outline their call for a phase-out of all nuclear power plants.

Several antinuclear activists see this week as a major turning point in what they predict will be a long struggle. "This is our Vietnam," Harvey Wasserman, one of the organizers, said. "It's the issue of the next two decades."

Most antinuclear activity has been in rural areas near power plants or on college campuses, and the movement has had trouble attracting support in large cities. David Fenton, Wasserman and other organizers speak of folloling New York with similar events in Chicago and other cities.

Fenton, one of the eight board members of Musicians United for Safe Energy Inc. (MUSE), which is putting on the concerts, said ticket sales should bring a profit of about $750,000, and more money will be raised by a two-record album and possibly a movie of the concerts.

In part because they are aware that few dollars reached the intended recipients from benefits for Bangladesh and Reuben (Hurricane) Carter, the organizers have been planning for almost a year to be sure the money doesn't leak away.

The MUSE foundation will distribute the profits. About one-third will go to national antinuclear groups, one-third to local organizations and one-third to a media campaign for public education.

All the concert performers, who include Bruce Springsteen and the E Street Band, James Taylor, Jackson Browne, Bonnie Raitt, Ry Cooder and Peter Tosh, are donating their talent but will be reimbursed for hotel and travel costs.

MUSE initially planned three concerts, beginning Wednesday night. A fourth has been added and a fifth on Sunday night still may be added, Fenton said. The concerts are nearly sold out at $15, $15.50 and $18.50 a seat, he said.

In addition to four hours of music, the concerts will include an 18-minute film called "Save the Planet." The film contains early U.S. government film footage on the benefits of "irradiated food" and the beauty of mushroom clouds as well as footage of Three Mile Island.