So the density of the dot conveys something about how far away (or close) it is to the center of reference? Holy cow! Doing the calculations is amazing enough, but imagine what it took to figure out the theory in the first place. All hail Lawrence Bragg!
@mford610 Thankfully computers are taking over the heavy lifting when it comes to the math. (No more printing out absorption peaks and cutting out the paper with a scalpel and weighing them to do integrations). As far as the blurry dots are concerned, I always think of it like taking a film picture. When you first take take a photo, the image is imprinted as a negative on film with all the colors "flipped". To print the photo, you need to reverse those inverted colors. The same is true with the "dots", except instead of inverting colors, you are "inverting" xyz coordinates. Having seen the math and done a few examples by hand, I am very, very thankful that is not necessary any more!
My knowledge of xray diffraction extends only as far as Rosalind Franklin/Francis Crick and the discovery of the structure of DNA. The phrase "monoclinic, face-centered" launched Crick into history. As an artist I have struggled to understand how a pattern of blurry dots translates into 3D information, but it is beyond me. Your assembly is the most informative presentation I have seen (though I have not seen many). I assume these days the computer and AI has taken over from rulers and scribbled calculations. As Max Perutz would say, "that's not fair!"
@mford610 Correct, monoclinic can either be base centered or primitive. While one can additionally draw a body centered monoclinic cell, this centering is merely a translation of the base centered cell. I hope that answers your question!
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So the density of the dot conveys something about how far away (or close) it is to the center of reference? Holy cow! Doing the calculations is amazing enough, but imagine what it took to figure out the theory in the first place. All hail Lawrence Bragg!
@mford610 Thankfully computers are taking over the heavy lifting when it comes to the math. (No more printing out absorption peaks and cutting out the paper with a scalpel and weighing them to do integrations). As far as the blurry dots are concerned, I always think of it like taking a film picture. When you first take take a photo, the image is imprinted as a negative on film with all the colors "flipped". To print the photo, you need to reverse those inverted colors. The same is true with the "dots", except instead of inverting colors, you are "inverting" xyz coordinates. Having seen the math and done a few examples by hand, I am very, very thankful that is not necessary any more!
My knowledge of xray diffraction extends only as far as Rosalind Franklin/Francis Crick and the discovery of the structure of DNA. The phrase "monoclinic, face-centered" launched Crick into history. As an artist I have struggled to understand how a pattern of blurry dots translates into 3D information, but it is beyond me. Your assembly is the most informative presentation I have seen (though I have not seen many). I assume these days the computer and AI has taken over from rulers and scribbled calculations. As Max Perutz would say, "that's not fair!"
@mford610 Correct, monoclinic can either be base centered or primitive. While one can additionally draw a body centered monoclinic cell, this centering is merely a translation of the base centered cell. I hope that answers your question!
monoclinic is base centered?