The top student must be diligent.

Chapter 140 Learning and Thinking about Computational Materials Science

Xiao Yi smiled and said, "After I finish this, I will probably have to run it on your old antique server, just for a small-scale calculation."

Luo Mingya was helpless and said, "Okay, then I can only use that server reluctantly later."

"She seemed to have said just now that dogs are not even needed." Liu Chao whispered to Xu Ming beside him.
Unfortunately, Luo Mingya heard it. She looked over and said, "Well, Junior Brother Liu, you and Xu Ming will be responsible for the garbage and sanitation of the laboratory this month."

"what?"

Liu Chao's eyes suddenly widened.

Then he slapped himself on the mouth and said, "Why can't I control my mouth?"

Xu Ming beside him laughed and patted his shoulder: "Good brother! We share happiness and difficulties together!"

……

Soon, Xiao Yi optimized their algorithm. Without further ado, they returned to the computer room to conduct a small-scale simulation of the new algorithm.

Because it was just a small-scale simulation that didn't take long to run, they got the results quickly.

After Xiao Yi's optimization, the utilization efficiency of computing resources increased by almost 20%, and both the convergence speed and calculation accuracy were improved.

Although this cannot directly help them to reach a research result, it can greatly speed up the research process and save a lot of research time. From this point of view alone, it is very rare.

"Awesome! God Xiao."

Seeing this result, Xu Ming’s eyes widened and he exclaimed in surprise.

Others also looked surprised.

Luo Mingya said: "Thank you, Xiao Xuedi."

Xiao Yi smiled and waved his hands: "It's nothing. After all, I am also a member of the research group now. Optimizing algorithms and so on are just my job."

"Sun Lina, look at how humble Xiao Shen is. What about you? He's playing around again!"

Luo Mingya turned around and started to confront Sun Lina, but at this time Sun Lina had already picked up the switch and started playing again.

"Don't cue, don't cue." Sun Lina waved her hand: "The world belongs to you young people. Let you young people handle this kind of thing."

However, Luo Mingya silently took out his mobile phone and started playing a recording.

"Who is not an 18-year-old pure, lovely and beautiful girl~"

"Ahhhh!!!"

Sun Lina jumped up immediately: "Luo! Ming! Ya! I'm going to fight you!!"

Then she rushed forward and tried to snatch Luo Mingya's cell phone.

Xiao Yi and the others looked at the scene in amazement.

The voice in Luo Mingya’s phone just now... seems to be the voice of Teacher Sun, right?

"It's over. Will Teacher Sun kill us to silence us?"

Liu Chao hugged his head, his face full of horror.

……

The farce ended quickly, and their discussion for the day ended there.

The laboratory still needs to carry out work. After all, they have not only one project, but also many other projects.

According to what Xiao Yi heard from Xu Ming and the others, Luo Mingya, as the actual controller of this laboratory, was working on at least three projects at the same time.

Their topic is currently one of the more important ones. If successful, they will have a good chance of being nominated for the National Natural Science Award.

As for their younger classmates, if they have slightly better topics, Luo Mingya will also provide them with certain help, whether it is funding or guidance.

All in all, their senior sister is actually a very good senior sister to them. Perhaps the only problem is that she can't tolerate any flaws in her eyes. If they are lazy, she will definitely point fingers at them.

So, as soon as the discussion was over, they returned to the laboratory and continued their task.

As for Xiao Yi, he naturally had nothing to do. After understanding the subject, he also looked at the mathematical model that had been established.

The only task left is to study.

And this is something that needs to be learned.

First of all, he has to start with some basics. At least he has to understand the prerequisite knowledge about computational materials science, especially the related content about density functional theory and first principles calculation.

After all, he had to first understand the principles of the mathematical model.

Fortunately, Luo Mingya not only recommended the textbooks he needed to read, but also lent him the books she had read before. After all, the library has not officially opened yet, so it is definitely impossible to borrow books. If he wants to buy a book, it may take several days for it to arrive.

As a genius, Luo Mingya knew very well that if Xiao Yi had less study time for a few days, he would lose a lot of knowledge.

The sooner Xiao Yi understands the principles of computational materials methods such as density functional theory and first principles calculations, the sooner he can provide them with more help.

Just like that, time passed quietly.

…
Library study room. Although the library was not open, the study room was open to the public.

Of course, because school has not officially started yet, the study room is empty. Those who can study here now are either those who did not go home during the Chinese New Year, or those who have come back to study before the holiday is over.

Xiao Yi's entry did not attract anyone's attention. He carried his schoolbag, found a corner, and opened the book "Density Functional Theory: A Practical Introduction" in his hand, a classic book on density functional theory. The English name of density functional theory is Density Functional Theory, abbreviated as DFT.

Judging from the marks on the book, it can be seen that Luo Mingya has turned every page of the book many times.

However, judging from the appearance, the book is still neat despite having been flipped many times.

Turning to the first page, he officially began to study.

Density functional theory is the cornerstone of computational materials science. It is the birth of this theory that formally introduced the study of materials science onto computers.

DFT avoids the difficulties of directly solving the complex multi-body Schrödinger equation by using electron density to describe the ground state properties of multi-electron systems.

Of course, as a top mathematician, after reading it a few times, Xiao Yi easily began to think about how to connect the variational principle in mathematics with the rigorous expression in DFT.

In addition to the contents of the book, it also includes notes written by Luo Mingya.

He glanced at two lines of notes: [The Kohn-Sham equation simplifies a multi-electron problem to a single-electron problem, but the choice of the exchange-correlation energy functional is crucial.]

[LDA and GGA have different scopes of application, but how to balance accuracy and computational cost in actual calculations is a problem that requires in-depth research. ]

Xiao Yi nodded slightly. These notes really hit the point.

In general, all theories of computational materials science face the problem of balancing computational accuracy and computational cost. For example, first-principles calculations have relatively better computational accuracy, but at the same time, they also have very high requirements for computational cost. This is a problem for any research group. After all, everyone has limited funding or time.

On Earth Online, no one can open a cracked version.

Time passed slowly, and the book also gave an example about the electronic structure of silicon crystals.

He pondered over it over and over again, thinking about the example from many aspects.

The more he thought about it, the more he could appreciate the impact of different functionals on the calculation results.

As a mathematician, and a talented one at that, he couldn't help but start thinking about whether he could improve the construction of functionals through mathematical optimization methods.

"The basic idea of ​​density functional theory is to express the energy of a multi-electron system as a functional of the electron density. The Kohn-Sham equation simplifies the electronic system into the movement of a group of non-interacting electrons in an effective potential field, which effectively reduces the computational complexity."

"Obviously, the solution to the Kohn-Sham equation depends on the exact form of the exchange-correlation energy functional. If this is possible..."

Xiao Yi's thoughts became more and more profound.

From density functional theory to first principles, computational materials science also includes many other methods, such as molecular dynamics and Monte Carlo simulation.

Of course, he did not forget to study other basic theories, including the basics of materials science, quantum mechanics and so on.
Just like that, a few days passed quietly.

……

a few days later.

In the Entrepreneurship Center.

"Master, what do you do for a living?"

Liu Chao looked at the masters who were moving the server in front of him and suddenly asked.

There was silence for a moment, and everyone present looked at him.

Liu Chao suddenly realized what was going on, then coughed awkwardly twice and said, "Um... I'm going to the bathroom."

"I'll go with him."

Xu Ming, who was a little overwhelmed, ran over and soon heard a hearty laugh coming from the other side of the corridor.

Xiao Yi held back his laughter and continued watching from the side.

This was the server cluster he bought at a huge cost of 500 million yuan, and Xu Ming provided a lot of suggestions on it.

After entering the venue, the masters began to assemble the servers.

Well... 500 million should be enough for a while, right?
Xiao Yi began to ponder in his heart.
Just at this moment, his cell phone rang, and he saw it was a call from Boss Huang.

"Haha, Xiao Yi, I have already transferred all the 150 million royalties from my side to you."

Hearing the other party's words, Xiao Yi smiled and said, "Okay."
Not bad, although 500 million was spent, 150 million was recovered, which is not bad.

This usage fee is the activation fee for each mining machine using Yishui Bit.

After using it for free for a few days, Mr. Huang had naturally seen how powerful this software was, so as soon as the free trial period was over, he paid the usage fees for nearly 3 mining machines in his mine.

150 million may seem like a lot, but it’s actually not much at all.

According to the current Bitcoin price of $55000, even without Yishui Bit, his mine would have a daily revenue of around RMB 350 million. Now with Yishui Bit, it has directly reached 600 million. It’s only 150 million, and he earned it back in one day.

"Also, Xiao Tiancai, I have already promoted Yishui Bit for you. According to what you said before, wasn't it going to be available for download today? But I haven't seen you open it yet. Now people from other mining farms are calling me and asking me what's going on."

"I estimate that this time, at least 20 mining machines will use your software." Well, you can try
You are not alone

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(End of this chapter)