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Choosing capacitor for LM6100 ethernet PHY XTAL


I want to use a crystal with the following characteristics for the LM3s6100 PHY

Load capacitance = 18pF

Freq tolerance       = 50ppm

Freq                         = 25Mhz

Link                         = http://in.element14.com/jsp/search/productdetail.jsp?sku=1611791

The Datasheet of the MCU shows there is a load capacitance of  CL = 50 pF

By using the equation CL = (C + (CP+CI)) / 2   assuming Cp = 5pF

Therefore 50pF = (C + 55pF)/2       

Hence C = 10pF Approx?

Did I get it right ?Should I connect a 10pF capacitor to the external crystal?

Please let me know your views



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