Eurico Angeloni, an art student who has given up on the Communist Party, brings cheer to some of Italy's most conservative politicians. But he and his associates also frighten a growing number of Italians.

"The Communists have compromised themselves and have become just as corrupt as the other parties," Angeloni said, standing in the dim light of a single naked bulb on the second floor of the once-fashionable Hotel Stella in central Florence. "They have given up on revolution. It is up to us to make the revolution now."

Closed three years ago, the Stella was boarded up and empty until it was taken over by the bearded Sicilian student and 110 other young people three months ago to protest the lack of student housing here. The municipal government, headed by the Communists, has kept off electricity and water but made no other moves against the commune.

"It makes no difference that the Communists are in control here," said a young woman who is in her fourth year at the university but who keeps reducing her course load rather than graduate and join the ranks of the unemployed. "They let the speculators close down buildings to increase rents, too."

A rising tide of radicalization and violence is seriously challenging the Italian Communist Party's commitment to moderate "Eurocommunist" policies that now appear to be costing the party electoral support.

After watching the Communists quietly cooperate with the minority Christian Democrat government for the past nine months, students and others who once flocked to the Communist banner appear now to be supporting extremist groups or abandoning party politics altogether in growing numbers.

That tentative but spreading impression encourages some Christian Democrats and Western diplomats who hope the Communists have peaked in their drive for power. One group of young Christian Democratic parliamentarians seeks to provoke new national elections in hopes of erasing the Communist gains of recent years.

That same impression of the Communists' peaking frightens other equally conservative political activists and analysts.

"For a decade, we've been watching them grow into the country's second largest party and worrying about all the members they were getting," said a middle-level civil servant. "Now we have to worry about members they are not getting. Those are the people who go completely outside the system now."

Serious urban violence flared for the fourth time is three months Thursday when a young woman was shot and killed in Rome during rioting after police broke up a political meeting.

Prison breaks, kidnapings and other violent crimes have become so frequent that newspapers and citizens complain of a spreading breakdown in law and order.

"We are in a gradual and decentralized version of France's May 1968," said one senior police official, referring to the spontaneous social upheaval in Paris that pushed the French government to the edge of collapse nine years ago. "Italy is a much more flexible society, so it takes longer for it to show up."

Confronted by the pressures of public disorder, new economic problems and the growing discontentent of students and at least 1 million unemployed, Christian Democratic Premier Gullio Andreotti has opened negotiations with all other parties, including the Communists, on a program of emergency measures to be carried out by his minority government.

The Communists, who pulled 34 per cent of the popular vote or only 4 per cent less than the Christian Democrats in last June's parliamentary election, have permitted Andreotti's government to survive by abstaining on bills that Andreotti has cleared with them.

Now Andreotti, who has established good working relations with Communist leaders, wants the Communists to commit themselves to a "programatic accord" encompassing increased police powers, reforms for the overwhelmed universities, and curbs on wage increases and government spending.

New compromises with the Christian Democrats will undoubtedly spark even more criticism from the left of the Communist Party's brand of Eurocommunism, which has greatly influenced other European Communist parties that have declared ideological independence from Moscow and endorsed democratic reforms rather than revolution as the way to power.

Two senior Communist Party officials indicated in interviews, however, that the party was prepared to weather such criticism, reaffirm its commitment to moderate policies and perhaps support a new government headed by Andreotti.

"We have to come up with something that shows things are going to change," said Central Committee member Luciano Barka. "To get such an agreement, the Communist Party has to be ready to lose something. But so must the Christian Democrats. We both have to take risks."

Speaking shortly before a two-day Central Committee meeting began in Rome on Thursday to agree on a response to the Christian Democratic proposals, Barka listed a series of specific steps the Communists would agree to if the Christian Democrats would reciprocate with political compensation that could be sold to Communist supporters as proof that their cooperation was profitable for the party.

The communists were not asking to be taken into the Cabinet, said Barka, who is the party's top economic expert.

"We seek guarantees of permanent contact," between the party's leaders and their counterparts in the Cabinet, and assurance that the Communists will be treated as equals in Parliament, Barka said.

Other sources suggested that the Communists would accept a high-level parliamentary group, with watchdog functions over the Cabinet, as their price for substantial agreement on a new program for governing.

Barka and other Communist officials praise Andreotti's skill in keeping the government afloat, and it now appears certain that they will support his staying on to head the Cabinet, which may be reshuffled after the emergency program is agreed upon. The Carter administration signalled that it expects Andreotti to continue in office by announcing last week that he will visit Washington in July.

"We have cooperated in the reconstruction of Italy for the past 30 years, and our efforts have become known as Eurocommunism," said Florence Mayor Emilio Gabbugiani, who is also a member of the party's Central Committee. "We are prepared to continue. We do not think these groups and students on the left have a future."

Asked specificially about ending the open enrollment system - which has led to the swamping of Italian universities in recent years but remains sacred to student activists - the two Communist officials gave the first hints of support for a limiting of enrollment if the Christian Democrats propose it.

"You can't maintain open enrollment indefinitely if you don't have the structures to educate the students you are admitting," Gabbugiani said. "It is a problem that has to be reconsidered, especially for technical faculties that are overcrowded."

Such comments increase the feeling of some political analysts here that the Communists have decided to write off the radicalized students and other groups slipping out of their control and continue their campaign for respectability and middle-class support. Also, a stepped-up-law-and-order campaign might help the party by curbing the extreme leftist groups that seem a direct threat to the Communists.

After a student was shot and killed in disturbances in Bologna earlier this year, Communist officials refused to let the student's brother address a unity rally in that northern Italian city. Asked why, a Communist city councilman told a visiting newsman:

"Then we would have never got the Christian Democrats to come to the rally. We had to choose between the students and the Christian Democrats, and we chose the Christian Democrats.