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If we are talking in a technical context, then we use technical language. It would not be technically correct to say "honeycomb", but if that's not the context then there is nothing wrong with it. Personally I try to be as technical in my language as efficiently possible just to get me in the habit.


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ice is less denser than water because in ice the molecules arrange themselves in a rigid tetrahedral structure due to which cage like spaces remain in their bonding. But water molecules remain in linear bonding form. As the volume of ice becomes greater, it is less denser.


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Let $N(x)$ be the cumulative number of distinctive neighbours in a distance $x$ for a certain point $A$ (all points with a distance of $x$ or less) and $n(x)$ be the distributive number of neighbours (distinctive points with the distance of exactly $x$). $N(x) = n(0) + n(1) + \ldots + n(x)$ $n(0) = 0$ $n(x) = 3*x$ $N(x) = \sum_0^x n(x) = \sum_0^x 3x = ...


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Here's an image of a hexagonal lattice to help you count http://www-personal.umich.edu/~sunkai/teaching/Winter_2013/hexagonal.png You can image the lattice being infinite in extent outside the image. So pick any point and count its nearest neighbors. You count six. Now pick another point and count them? Do you notice a pattern? You can be sure that this ...


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Yes, that certainly seems like a rather odd question. Given that the crystal is BCC, that information alone means that there are 2 atoms per cell, and the atomic packing factor is $\pi\sqrt{3}/8\approx 0.680$. The density and molar mass are irrelevant additional pieces of information. A sensible thing to ask for given those three pieces of information ...


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It is not thermodynamics that controls crystal formation at the atomic level, but quantum mechanics. Large crystals, from diamonds to clear ice crystals are a macroscopic manifestation of the underlying quantum dynamical level. The molecules that build up the crystal have such field properties, dipoles and quadrupole and even higher moments that have ...


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Well, when we talk of stability of systems, at least for equilibrium systems, we require the free energy to be bounded below and be convex. As the free energy is obtained by a Legendre transformation (which preserves convexity), the energy functional is required to be convex. This essentially allows us to minimize energies to find ground states. Within the ...


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There's a nitinol wire that stiffens when warm and softens when cool. It's been used in various patented heat engine applications. see this reference http://www.imagesco.com/articles/nitinol/09.html


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Because orthorhombic has a higher symmetry. Both orthorhombic and monoclinic have unit cells with unequal edge lengths ($a \ne b \ne c$). All of the unit cell angles are 90 degrees for orthorhombic ($\alpha = \beta = \gamma = 90^{\circ}$). However, for monoclinic, one of the angles is not $90^{\circ}$ - this reduces the symmetry of the crystal. While you ...



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