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IDEAL CHAIN

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The ideal chain or freely jointed chain is assumed. Each monomeric addition can orient the new monomeric repeat group in any direction (no constraint on angle) and growing polymer chain can polymerize through space occupied by polymer (no excluded volume).

To grow each new monomer, spherical coordinates are used, setting r=1 and making θ and φ random angles (in radians) from 0 to 2π.

100 units are polymerized. The displacement length (see End to End Distance) is calculated and reduced to an integer. The process rounds all numbers down.

Clicking a button below adds the number of polymers requested to the growing distribution. Clicking "1 polymer" several times shows the randomness of the displacement lengths (end to end distances). Clicking "1000 polymers" or "5000 polymers" adds polymers much faster.
    For 5000, the browser program may give a message that a script is taking a long time, and ask if you want to abort the script. If you choose "no" the polymerizations will continue. For most computers, the total time should be less than a minute.



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The average length is - - - .

The number of polymers is - - - .



An example for 1000 polymerizations:



An example for 5000 polymerizations:



An example with 25,000 polymerizations is shown below. The probability density for a Maxwell Boltzmann distribution was added to the spreadsheet for comparison to distribution of values for displacement length.



In the graph below, "Norm" (blue) refers to the normalized values. Norm values were calculated by taking the number of occurances, and dividing by 25,000. The "theo" values are theoretical values calculated from the above probability density function. The only variable is "a".

Throughout the slideshow, the variable "a" changes, starting at 1 and ending at 5.25. For each slide, the value of a is shown in the upper right corner.



The shape is similar, but not perfectly congruent, and tentatively the program is considered to have a flaw.

A second Ideal Chain page was constructed.