Christopher Harrisson, 82, was found guilty of murdering his ex-partner – fellow academic Dr Brenda Page.

He forced entry to the Aberdeen flat into which Dr Page had moved after fleeing their abusive marriage. Her body was discovered on 14 July 1978 by a concerned colleague and a neighbour.

Harrisson spent decades denying his crime but prosecutors from the Crown Office were able to prove his guilt using DNA examination and forensic techniques.

Biological samples taken from the sheets of Dr Page’s bed were re-examined using state-of-the-art analysis.

National procurator fiscal for homicide and major crime, David Green, said he hoped the sentence brought some degree of comfort to the family of Dr Page.

Mr Green said: “The relatives of Dr Brenda Page have waited a very long time for justice and our thoughts are with them as they come to terms with today’s outcome. Christopher Harrisson took the life of their loved one and subjected them to further torment by maintaining his pretence of innocence for many years.

“Our skilled prosecutors were able to ensure that a jury saw through his callous deception. Evidence collected at the time painted a picture of a bullying and manipulative man but it has taken breakthroughs in science and forensics to allow us to prove the case beyond any doubt.

“A man once recognised as a skilled scientist himself has been brought to justice through scientific expertise.”

A jury at the High Court in Aberdeen heard evidence that Dr Page was terrified of her former husband and had told associates she feared he would one day kill her.

Hand-written letters detailed some of the abuse to which she was subjected by Harrisson. In one, Dr Page asked her lawyer to ensure she receive a thorough post-mortem should she ever die suddenly.

In a letter from Harrisson to Dr Page, he acknowledged his “rages of which you are afraid”.

Thousands of documents were re-examined in preparing the prosecution. By the time Harrisson stood trial, many witnesses were in their 70s and 80s, and several gave evidence by live television link from other locations in the UK in order to avoid travel to the High Court in Aberdeen.

Mr Green, who leads on murder investigations for COPFS, added: “COPFS does not view any unresolved homicide as ‘closed’, and the public should be assured we will not stop seeking justice, no matter how long ago the offences took place.

“I would urge anyone with any information on unresolved murders to report it to the police, confident that we will treat any report we receive with the utmost gravity.

“Harrisson is an old man now but he is finally facing the consequences of his cruelty and violence.”

The jury at the High Court in Aberdeen agreed with prosecutor, advocate depute Alex Prentice KC, that Harrisson killed his former wife in her own home by striking her on the head and body.