Virial Expansion Approximation of of Lennard Jones Potential

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SUMMARY

The discussion centers on the numerical evaluation of the second virial coefficient, B2(T), derived from the Lennard-Jones potential. The integral expression provided, $$B_2(T)=2\pi N\int_{0}^{\infty} (1-e^{-\beta E_0((\frac{r_0}{r})^{12}-2(\frac{r_0}{r})^6)})r^2dr$$, requires numerical methods for evaluation. Participants suggest using Taylor's Expansion for the exponential function to simplify calculations and recommend graphing the function with software tools to visualize behavior near zero.

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Diracobama2181
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Homework Statement
Numerically evaluate the second viral coefficient of the Lennard-Jones Potential. The result should be expressed in the form of a dimensional constant times
a dimensionless function of the dimensionless variable $$ E_0 \beta$$
Relevant Equations
$$U=E_0((\frac{r_0}{r})^{12}-2(\frac{r_0}{r})^6)$$
$$B_2(T)=2\pi N\int_{0}^{\infty} (1-e^{-\beta E_0((\frac{r_0}{r})^{12}-2(\frac{r_0}{r})^6)})r^2dr$$
I get
$$B_2(T)=2\pi N\int_{0}^{\infty} (1-e^{-\beta E_0((\frac{r_0}{r})^{12}-2(\frac{r_0}{r})^6)})r^2dr$$
as the coefficient. I was just unsure how to evaluate it numerically from here. Any suggestions would be appreciated. Thank you.
 
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Try expanding exponential function around 0 to few orders. Also,look at the graph of function (using any software) why you need Taylor's Expansion around 0
 
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