Nav: Home

Growing perfect crystals by filling the gaps

May 30, 2016

Crystals are solid materials composed of microscopic building blocks arranged in highly ordered patterns. They have countless applications, ranging from metallurgy to jewellery to electronics. Many of the properties that make crystals useful depend on the detailed pattern of arrangement of their constituents, which, in turn, is highly sensitive to the details of the interaction between the building blocks. In molecular and atomic crystals the interparticle forces are fixed by Nature, and the only way of tuning the microscopic arrangement is to either vary the external conditions (temperature, pressure, etc.) or change the particles themselves. By contrast, insoft matter Physics , where the building blocks are orders of magnitude larger and much more complex than atoms, it is possible to design and engineer building blocks with extremely tunable properties. Consequently, much effort has been devoted to the synthesis of colloids that self-assemble into highly symmetric patterns with technologically relevant properties. For instance, there exist specific crystal lattices that exhibit very exciting optical properties, the so-called photonic crystals - periodic structures that allow certain bands of wavelengths of light to propagate through their interior while blocking other ones.

A natural example of a photonic crystal is the opal, whose fascinating coloration is due to the way the light interacts with its microscopic structure of colloidal particles arranged on a regular lattice. The multicolored iridescence of the precious opal, the source of its charming appearance, is due to the presence of several small crystals, known as crystallites, which are randomly oriented with respect to the one another. In addition, the assembly of colloidal crystals is often confounded by polymorphism: "different structures are characterised by comparable thermodynamic stabilities, making it difficult to produce a single morphology at will", says Christos Likos from the Faculty of Physics of the University of Vienna.

The resulting lack of long-range order is detrimental for many applications. Accordingly, strategies need to be developed that enhance the growth of long-ranged, monocrystalline samples in (real or numerical) experiments. Accordingly, scientists have been working hard to deveop strategies that enhance the growth of large, monocrystaline structures. Employing computer simulations, a new method has now meen deveoped that allows the assembly of technologically relavant, non-polymorphic crystals. "the system crystallises into a mixture of difference micocrystals. However, the competing structures assembled by the colloids have different geometries and different internal void distributions. This difference can be exploited by tuning the size of polymer additive to interact uniquely with the void symmetry of the desired crystal, effectively stabilising it against the competitor"., explains Lise-Meitner Fellow Lorenzo Rovigatti, working at the group of Christos Likos.

The results of the research team serve not only to illustrate an alternative to existing approaches which, in many cases, produce unsatisfactory results, but also to guide experimental realizations of highly-ordered colloidal open crystals in the near future.
-end-
Publication in "ACS Nano"

Nathan A. Mahynski, Lorenzo Rovigatti, Christos N. Likos, and Athanassios Z. Panagiotopoulos
DOI 10.1021/acsnano.6b01854

The project was supported by the Austrian Science Fund (FWF) through the Lise-Meitner Fellowship M 1650-N27.

University of Vienna

Related Physics Articles:

Diamonds coupled using quantum physics
Researchers at TU Wien have succeeded in coupling the specific defects in two such diamonds with one another.
The physics of wealth inequality
A Duke engineering professor has proposed an explanation for why the income disparity in America between the rich and poor continues to grow.
Physics can predict wealth inequality
The 2016 election year highlighted the growing problem of wealth inequality and finding ways to help the people who are falling behind.
Physics: Toward a practical nuclear pendulum
Researchers from Ludwig-Maximilians-Universitaet (LMU) Munich have, for the first time, measured the lifetime of an excited state in the nucleus of an unstable element.
Flowers use physics to attract pollinators
A new review indicates that flowers may be able to manipulate the laws of physics, by playing with light, using mechanical tricks, and harnessing electrostatic forces to attract pollinators.
Physics, photosynthesis and solar cells
A University of California, Riverside assistant professor has combined photosynthesis and physics to make a key discovery that could help make solar cells more efficient.
2-D physics
Physicist Andrea Young receives a 2016 Packard Fellowship to pursue his studies of van der Waals heterostructures.
Cats seem to grasp the laws of physics
Cats understand the principle of cause and effect as well as some elements of physics.
Plasma physics' giant leap
For the first time, scientists are looking at real data -- not computer models, but direct observation -- about what is happening in the fascinating region where the Earth's magnetic field breaks and then joins with the interplanetary magnetic field.
Nuclear physics' interdisciplinary progress
The theoretical view of the structure of the atom nucleus is not carved in stone.

Related Physics Reading:

Basic Physics: A Self-Teaching Guide
by Karl F. Kuhn (Editor)

The fast, easy way to master the fundamentals of physics

Here is the most practical, complete, and easy-to-use guide available for understanding physics and the physical world. Even if you don't consider yourself a "science" person, this book helps make learning key concepts a pleasure, not a chore. Whether you need help in a course, want to review the basics for an exam, or simply have always been curious about such physical phenomena as energy, sound, electricity, light, and color, you've come to the right place! This fully up-to-date edition of Basic Physics:
* Has been... View Details


Seven Brief Lessons on Physics
by Carlo Rovelli (Author)

Instant New York Times Bestseller

“One of the year’s most entrancing books about science.”—The Wall Street Journal

“Clear, elegant...a whirlwind tour of some of the biggest ideas in physics.”The New York Times Book Review

 
This playful, entertaining, and mind-bending introduction to modern physics briskly explains Einstein's general relativity, quantum mechanics, elementary particles, gravity, black holes, the complex architecture of the universe, and the role humans play in this weird and wonderful world.... View Details


Fundamentals of Physics: Mechanics, Relativity, and Thermodynamics (The Open Yale Courses Series)
by R. Shankar (Author)

Professor R. Shankar, a well-known physicist and contagiously enthusiastic educator, was among the first to offer a course through the innovative Open Yale Course program. His popular online video lectures on introductory physics have been viewed over a million times. In this concise and self-contained book based on his online Yale course, Shankar explains the fundamental concepts of physics from Galileo’s and Newton’s discoveries to the twentieth-century’s revolutionary ideas on relativity and quantum mechanics.
 
The book begins at the simplest level, develops the basics,... View Details


Physics Equations & Answers (Quick Study Academic)
by Mark Jackson (Author)

Essential tool for physics laws, concepts, variables and equations, including sample problems, common pitfalls and helpful hints.

View Details


Physics of the Impossible: A Scientific Exploration into the World of Phasers, Force Fields, Teleportation, and Time Travel
by Michio Kaku (Author)

Teleportation, time machines, force fields, and interstellar space ships—the stuff of science fiction or potentially attainable future technologies? Inspired by the fantastic worlds of Star Trek, Star Wars, and Back to the Future, renowned theoretical physicist and bestselling author Michio Kaku takes an informed, serious, and often surprising look at what our current understanding of the universe's physical laws may permit in the near and distant future.Entertaining, informative, and imaginative, Physics of the Impossible probes the very limits of human... View Details


The Cartoon Guide to Physics (Cartoon Guide Series)
by Larry Gonick (Author)

If you think a negative charge is something that shows up on your credit card bill -- if you imagine that Ohm's Law dictates how long to meditate -- if you believe that Newtonian mechanics will fix your car -- you need The Cartoon Guide to Physics to set you straight.

You don't have to be a scientist to grasp these and many other complex ideas, because The Cartoon Guide to Physics explains them all: velocity, acceleration, explosions, electricity and magnetism, circuits -- even a taste of relativity theory -- and much more, in simple,... View Details


No bullshit guide to math and physics
by Ivan Savov (Author)

Often calculus and mechanics are taught as separate subjects. It shouldn't be like that. Learning calculus without mechanics is incredibly boring. Learning mechanics without calculus is missing the point. This textbook integrates both subjects and highlights the profound connections between them.

This is the deal. Give me 350 pages of your attention, and I'll teach you everything you need to know about functions, limits, derivatives, integrals, vectors, forces, and accelerations. This book is the only math book you'll need for the first semester of undergraduate studies in... View Details


Storm in a Teacup: The Physics of Everyday Life
by Helen Czerski (Author)

A physicist explains daily phenomena from the mundane to the magisterial.

Take a look up at the stars on a clear night and you get a sense that the universe is vast and untouchable, full of mysteries beyond comprehension. But did you know that the key to unveiling the secrets of the cosmos is as close as the nearest toaster?

Our home here on Earth is messy, mutable, and full of humdrum things that we touch and modify without much thought every day. But these familiar surroundings are just the place to look if you’re interested in what makes the universe tick.... View Details


Seven Brief Lessons on Physics

View Details


Schaum's Outline of College Physics, 11th Edition (Schaum's Outlines)
by Frederick J. Bueche (Author), Eugene Hecht (Author)

The ideal review for your college physics course

More than 40 million students have trusted Schaum’s Outlines for their expert knowledge and helpful solved problems. Written by renowned experts in their respective fields, Schaum’s Outlines cover everything from math to science, nursing to language. The main feature for all these books is the solved problems. Step-by-step, authors walk readers through coming up with solutions to exercises in their topic of choice.

Outline format facilitates quick and easy review of college physics 984 solved problems Hundreds more... View Details

Best Science Podcasts 2017

We have hand picked the best science podcasts for 2017. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Simple Solutions
Sometimes, the best solutions to complex problems are simple. But simple doesn't always mean easy. This hour, TED speakers describe the innovation and hard work that goes into achieving simplicity. Guests include designer Mileha Soneji, chef Sam Kass, sleep researcher Wendy Troxel, public health advocate Myriam Sidibe, and engineer Amos Winter.
Now Playing: Science for the People

#448 Pavlov (Rebroadcast)
This week, we're learning about the life and work of a groundbreaking physiologist whose work on learning and instinct is familiar worldwide, and almost universally misunderstood. We'll spend the hour with Daniel Todes, Ph.D, Professor of History of Medicine at The Johns Hopkins University, discussing his book "Ivan Pavlov: A Russian Life in Science."