Zijie Yan, the University of North Carolina associate professor who was fatally shot on campus Monday, is being remembered as a creative force who was generous with his time and talents in both his professional and personal life.  
Yan, who taught applied physical sciences, was a sweet, “dedicated father,” who was passionate about his work, friends and former colleagues said. 
“He was a quiet person with a constant smile,” Doug Chrisey, Yan’s mentor at Rensselaer Polytechnic Institute, where he got his Ph.D., told NBC News. “He was a great cook, great chef. He loved to fish. And I know he loved to be with his daughters.” 
Yan was shot on the Chapel Hill campus at Caudill Labs, a chemistry building. UNC’s police chief, Brian James, said at a news conference Tuesday that the armed suspect headed directly to the victim and left immediately after shooting him. The suspect, Tailei Qi, a graduate student at the school, was charged with first-degree murder and possession of a gun on educational property. 
Chrisey, who has known Yan since 2006, said that over the years they had stayed in touch and that he has kept photos of Yan with his family. Their interactions were always sunny, the professor said, which made news of Yan’s death particularly shocking. 
“He was a positive person and he had a great deal to offer,” Chrisey, a physics professor who’s now the chair of materials engineering at Tulane University, said. “There’s no reason why it makes sense for it to be him. I can’t imagine he ever said a cross word to me, even once.” 
Yan excelled in his professional endeavors, Chrisey said, adding that while he was “aggressive” about his work, he was never competitive or political. 
“He just felt like he had his own horse to ride and he was going to take the distance and not step in anybody else’s area of research,” Chrisey said. “In an academic environment, that’s also pretty unique to have someone be just so positive. I was on the phone with a UNC faculty member a little while ago and we were both crying on the phone about him.”
After getting his doctorate at RPI, Yan completed his postdoctoral studies at the University of Chicago in 2015. He went on to become an assistant professor at Clarkson University in upstate New York, before making his way to UNC. 
Norbert Scherer, a chemistry professor and Yan’s former postdoctoral adviser at the University of Chicago, echoed many of Chrisey’s thoughts. Scherer said that the pair’s work together helped push toward a “new science direction,” around “optical matter,” which consists of metallic nanoparticles bound together by light.
Scherer, who published roughly 15 peer-reviewed papers with Yan, said their collaborative yet challenging relationship helped mutually improve their work. 
“I always found interacting with him to be both really rewarding, but also the challenging process. And both of those things are what it should be,” Scherer said. “He was always really well prepared. And his ideas are very clearly thought out. … We would really bounce around and, in the positive sense, critique ideas. There was a lot of back and forth. It was a wonderful working relationship.”
Though Yan delighted in his own research, both of his former mentors emphasized that he took pride in helping students and budding scientists. Chrisey said he remembers when Yan helped mentor high school students in preparation for a science fair. And Scherer recounted how Yan, whose skills could intimidate students, would practice patience. 
“What I observed in how Zijie works is that he was very patient and devoted himself to people who were trying, even if they weren’t aspiring to his level of ability and insight, that if they tried, then he would really work diligently with them,” Scherer said. 
As friends, family, students and colleagues pay tribute to the late scientist, Chrisey said he hopes that people will see the world with the same attitude that Yan brought with him every day. 
“His smiling goodness diffused into everything he did, including being a very self motivated and very capable scientist,” he said. “It’s possible in this very imperfect world to have your own little space. You can make your little microcosm of positivity for the world.”
On Wednesday, the first day UNC students returned to classes, the school’s Bell Tower tolled at 1:02 p.m. in Yan’s memory. The university will also be holding a candlelight vigil later in the day to mourn his loss. 
“Dr. Zijie Yan was a good man and a dedicated scholar, and he was senselessly killed while doing his job,” said Peter Hans, president of the University of North Carolina school system. “I join everyone in the Carolina community in condemning this act of violence and standing shoulder-to-shoulder with Dr. Yan’s family, friends, students, and colleagues.” 

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