BERLIN (Reuters) - The expectations of investors of a possible Greek exit from the euro in the coming months, as measured in a snap poll on Sunday by Germany's Sentix research group, have not risen from the last poll taken a week earlier, Sentix said. In a lightning poll taken on Sunday from among 600 individual and institutional investors, the index was unchanged at 50 percent compared to a survey of 1,020 published on June 22 and conducted from June 18 to June 20. Greece's left-wing Syriza government had for months been negotiating a deal to release funding in time for its IMF payment. ...