Using a dynamic Monte Carlo method we investigated the thermodynamics of static and timehyphen;dependent properties of the freely jointed polymer chain with Lennardhyphen;Jones type intramolecular forces. The THgr; temperture is calculated tokBTHgr;/minus;=3.70plusmn;0.01 (minus; is the Lennardhyphen;Jones energy parameter). We give estimates for the equilibrium values of endhyphen;tohyphen;end distances, radii of gyration, and densities for chains consisting of up toN=63 segments and for various temperatures. The detailed structure of the extended coil state (Tgsim;THgr;) and the dense globular state (TTHgr;) are demonstrated by their average internal distances and their structure functions. The results seem to confirm the predicted scaling laws. Especially we found that forT=THgr; the mean size of the coil is sim;N1/2but the detailed structure is different from a random walk shape. Although the specific heat exhibits a maximum below the THgr; temperature, the finite size effects are too serious to confirm the predicted logarithmic divergency. The dynamics of our Monte Carlo method simulate the Rouse model. The density correlation function and the associated relaxation time are calculated. The results are consistent with dynamic scaling predictions. The segment correlation function exhibits the initial sim;t1/2behavior and the diffusional behavior sim;tat large times.
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