(CNN) -- Part of Robert Ferrante's job had been to manage a laboratory that conducted clinical trials using various drugs and chemicals. Until he was accused of using one of those substances -- cyanide -- to kill his wife. On Friday, a Pennsylvania jury determined that this accusation was well founded, convicting the University of Pittsburgh medical researcher and professor of murder in death of 41-year-old Autumn Klein. As juror Helen Ewing told reporters afterward, "It was very hard for me to accept and to believe that he could have done it. "But I felt that the facts were clear, and I couldn't argue with them."
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A Pennsylvania jury convicts Robert Ferrante of murder in his wife's death
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Ferrante, who managed a scientific lab, bought cyanide just before she fell ill
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Authorities say the wife, Dr. Autumn Klein, was killed by cyanide poisoning
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A juror says: "The facts were clear, and I couldn't argue with them"
Autumn Klein
Autumn Klein
According to a criminal complaint, several text messages sent between the couple suggest Ferrante urged @placeholder to try using creatine to get help her get pregnant.
Autumn Klein
Autumn Klein
Another neighbor of the couple, who asked not to be identified, said it was no secret that @placeholder wanted another baby.
Robert Ferrante
Robert Ferrante
Ferrante
The criminal complaint raises another source of friction: @placeholder confronted his wife three times within weeks of her death about whether or not she was having an affair.