Sail across the sea

Chapter 109 Does she understand local density functional analysis?
"That's great..., uh, what a pity!"

Gao Fan praised sincerely, but as soon as the words came out, he felt that something was wrong, so he quickly changed his words.

The teachers in the computing center are all saints. How many poor students have been saved by this regulation.

Gao Fan thought happily in his heart.

Yang Kai glanced at Gao Fan contemptuously, and said, "Don't pretend, I don't know what you think. You can't help me line up, but you can chat with me. I found that chatting with you It's still rewarding."

"Shouldn't this be avoided?" Gao Fan said, "When the night is dark and the wind is high, what can the two elders talk about? If Senior Brother Yang wants to chat with someone, let me introduce you to a girl. I I know a girl from the Department of Geology, who is very chatty..."

"Does she understand rare earths?"

"Understood, she told me that she followed her father to look for rare earth mines in Maolin since she was a child."

"So, does she understand local density functional analysis?"

"...This request is a bit high."

"Isn't that enough?" Yang Kaili said bluntly, "A person who doesn't understand local density functional analysis, what can I talk to her about?"

"Senior brother, you really want to live alone forever with your strength." Gao Fan complimented.

"Damn!" Yang Kai spat, and then said, "Gao Fan, I'm not kidding, I've been thinking about the principle of rare earth catalysis for a few days, and the more I think about it, the more I feel that there are a lot of things that can be done here.

"There are theories that the catalytic effect of rare earth elements is related to its unique highly localized f orbitals, but there is no convincing point of view on how this orbital improves catalytic activity.

"I want to build a complete electronic structure model of rare earth catalysts, and use the density functional theory corrected by the in-situ Coulomb interaction to perform calculations, which may be able to solve this mystery."

"Old Yang, you are playing too much, aren't you?" Gao Fan said dumbfounded.

Gao Fan understands what Yang Kai said.It is precisely because he understands that he knows how valuable and difficult this matter is.

Rare earth catalysis is a hot topic in both academia and industry, and everyone is trying to decipher the principle of rare earth catalysis in order to develop rare earth catalysts with better performance.

The research of many scholars is limited to theoretical conjectures. For example, it is believed that the paramagnetic structure of rare earth elements has a positive impact on the ortho-pair hydrogen conversion reaction, so it is speculated that dysprosium oxide and erbium oxide have greater activity, while lanthanum oxide is active. insufficient.

The defect of theoretical conjecture is that it cannot be accurately quantified.People can only find the optimal ratio of rare earth catalysts through experiments, and the cost of doing so is very huge.

Yang Kai's idea is to use computational quantum chemistry methods that have just emerged in the world, and use mathematical models to simulate the catalytic effect of rare earth elements to guide the development of rare earth catalysts.

Quantum chemistry, to put it simply, is to return the method of chemical research to the essence of chemical reactions, and to study the relationship between molecules from the level of atomic nucleus and electrons, for example, how many electrons are there around the nucleus, how these electrons rotate, and the relationship between electrons. How interactions occur, and how these interactions lead to bonding of atoms.

If all these problems can be summarized into mathematical formulas, the process of chemical reactions can be analyzed and the properties of compounds can be predicted only through mathematical calculations.

Since this method does not require real experiments, scholars can freely propose ideas for chemical reactions and demonstrate them from models.Wait until the demonstration is completed before doing experimental verification, which can greatly save time and cost.

The origin of quantum chemistry can be traced back to the 20s, but it was not until the 20s, with the popularization of computers, that scientists were able to truly complete these complex calculations, thus entering a stage called computational quantum chemistry.

In later generations, this kind of research method can be described as a household name, well, I mean it is a household name in the circle of chemists. For ordinary people, this method is simply more complicated than a bible.

Gao Fan understood this method, and he also knew that the model calculations for computing quantum chemistry in later generations need to be completed with the help of supercomputers with tens of billions of calculations per second.But what Yang Kai can rely on now is a so-called medium-sized computer with one million calculations per second, and he needs to queue for five hours to get a computer.

This is equivalent to thinking about going to the moon with a bow and arrow, isn't it too advanced?

"This matter is a bit difficult." Yang Kai nodded and said, "However, I think this direction should be correct. The concept of computational quantum chemistry was first proposed abroad in the 60s. We were a beat behind, but not far behind. It's too far.

"I have seen from the literature that foreign countries are making very fast progress in this direction and have made a lot of breakthroughs. If we don't hurry up to catch up now, when others run a little further, we will lose track of where we want to go. "

"So you plan to focus your research on computational quantum chemistry?" Gao Fan asked.

He remembered that when he met Yang Kai for the first time, Yang Kai said that the reason why he didn't go to graduate school was that he didn't find the direction he was interested in.But now, Yang Kai actually talked about catching up with the international advanced technology. This should be regarded as finding a direction, right?

Yang Kai said: "That's right, I've decided to take computational chemistry as my research direction. Speaking of which, I have to thank you for this. It wasn't you who proposed the topic of rare earth catalysts, so I wouldn't pay attention to this direction." .”

"Computational chemistry is a good direction." Gao Fan said, "But, Lao Yang, are you going to study this direction by queuing up every night to wait for the plane like this?"

Yang Kai said: "That's not the case. I can do the theory first, and when I need to check the calculation, I can apply for a computer through the department. In the past, our department didn't have this direction, so we didn't use computers. Now we have this direction. It is also reasonable to apply for a computer from the computing center."

"Well, that's the only way to go." Gao Fan said.

Although the computers of this era cannot be compared with those of later generations, Western scholars also use computers of this level. Everyone is competing on the same level. Yang Kai may not be unable to make some internationally leading results.

The only shortcoming is that Yang Kai does not have a computer that can be used whenever he wants like his western counterparts.According to Gao Fan's descriptions from old gentlemen in later generations, the laboratories of Chinese universities were equipped with personal computers in the mid-80s, and this was only limited to those laboratories with relatively sufficient funds.

"By the way, Gao Fan, you should also do this job." Yang Kai suddenly sent out an invitation, "Let's go to the Department of Mathematics to attend lectures, and then we will do computational quantum chemistry together. I believe that with your foundation and understanding, It will definitely do well.”

"I..."

Gao Fan hesitated, not knowing how to answer.

　I have tried my best... I really don't know what quantum chemistry is. I was desperately reading materials yesterday. If I made a mistake, please criticize it.If it doesn't work, I'll copy the book review and revise it.In addition, I recommend an old friend's vest book "Rebirth: Back to 1991 to Be the Richest Man", a vest of a very good old author, more than 400 catties, ah no, more than 400 million words, very fat...

　　


(End of this chapter)