SEEKING DIVORCE. Viktor Korchnoi, 52, tempestuous Soviet chess grand master who defected in 1976; and Beta Korchnoi, 50, who emigrated to Switzerland last year with their son Igor, 23, after the young man spent 30 months in a Siberian labor camp for refusing military service; after 25 years of marriage; in Wohlen, Switzerland. Korchnoi, who twice lost world championship matches to erstwhile Countryman Anatoly Karpov, pleaded with Leonid Brezhnev to allow his family to leave in 1978, though he was linked romantically with his Austrian-born manager, Petra Leeuwerik.

DIVORCED. Andrew Lloyd Webber, 35, pop musical composer (Evita, Cats); and Sarah Lloyd Webber, 30; on grounds of his adultery; after twelve years of marriage, two children; in London.

DIED. David Niven, 73, Scottish-born actor and author, who defined debonair for millions of moviegoers; apparently of amyotrophic lateral sclerosis, the progressive neuromuscular disorder often called Lou Gehrig's disease; at Chateau-d'Oex, Switzerland. A Sandhurst graduate and veteran of four years with the Highland Light Infantry, Niven resigned his commission in 1932 and became a New York liquor salesman. Influential acquaintances lured him to Hollywood, where he signed a seven-year contract with Movie Mogul Sam Goldwyn, despite having almost no acting experience. Niven served with distinction as a British commando officer in World War II, returned to star in more than 60 films, including Around the World in 80 Days, The Guns of Navarone and Separate Tables, in which he gave a 1958 Oscar-winning portrayal of a pathetic military impostor. His candid, bestselling memoirs (The Moon's a Balloon, Bring on the Empty Horses) abound with lightly told anecdotes of Errol Flynn's drunken revels and Greta Garbo's nude swims. Niven once described Hollywood as a "hotbed of false values. . . but it was fascinating, and if you were lucky, it was fun."

DIED. Luis Bunuel, 83, Spanish film maker considered one of the cinema's greatest artists; of bile duct disease; in Mexico City. Son of wealthy, religious parents, Bunuel and his friend Salvador Dali transfigured their fantasies in 1929 into one of the first surrealist films, Un Chien Andalou (An Andalusian Dog), a work of bizarre images including a man slashing a woman's eyeball with a razor. In 1930, L'Age d'Or (The Golden Age), with its brutal attacks on Roman Catholicism and bourgeois morality, established the ideological foundation for most of Bunuel's later films. A vehement antifascist, he left Spain in 1938, later won a Cannes Festival Grand Prix for Viridiana (1961) and an Academy Award for his scathing The Discreet Charm of the Bourgeoisie (1972). He said his films contained no deliberate symbolism but hedged, "Perhaps there are other meanings unknown by myself."

DIED. Raymond Massey, 86, gaunt, lanky, Canadian-born stage and screen actor remembered by a generation for his award-winning portrayals of Abraham Lincoln; of complications from pneumonia; in Los Angeles. Later audiences knew him best as the crusty but warmhearted Dr. Gillespie in NBC's Dr. Kildare TV series (with Richard Chamberlain in the title role).

DIED. Lynn Fontanne, 95-ish, willowy, perfectionist grande dame of the stage whose roles in sophisticated comedies opposite Husband Alfred Lunt made them the reigning couple of the American theater for two generations; of pneumonia; in Genesee Depot, Wis. The British-born Fontanne first acted professionally in 1905 and in 1922 married Lunt, with whom she appeared in 27 plays, including The Guardsman (1924) and Design for Living (1933). Before Lunt's death in 1977, the two declined a $1 million film offer with a cool, "We can be bought, but we cannot be bored."

DIED. Burrill B. Crohn, 99, pioneering gastroenterologist whose work in identifying and treating ileitis (intestinal inflammation) led to the ailment's becoming known as Crohn's disease; in New Milford, Conn. Crohn was one of the first physicians to conclude that anxiety and stress cause many gastric and intestinal disorders. This file is automatically generated by a robot program, so viewer discretion is required.