Hi, I tried simulating a high pass filter with a load impedance(A resistor). With a High output impedance, the voltage output of my RC high pass filter doesn't change with the addition of load and with a low load impedance, it changes -that is understandable.

So I went for an Opamp buffer. Still when I try to simulate it for a low impedance, the output voltage is clipped. Here is the image of my comparison:

Why is this happening? How can I create a buffer to drive such low impedances?

 

Well I didn't look at your schematic but maybe the op amp just can't supply so much current so it clips at the point where it reaches max .
Happened to me a few times when I was trying to have an op amp drive a 0.25 watt speaker before realising that no matter how many buffers I drive the signal through , the end stage just doesn't supply enough current

 

Hi, I tried simulating a high pass filter with a load impedance(A resistor). With a High output impedance, the voltage output of my RC high pass filter doesn't change with the addition of load and with a low load impedance, it changes -that is understandable.

So I went for an Opamp buffer. Still when I try to simulate it for a low impedance, the output voltage is clipped. Here is the image of my comparison:

Why is this happening? How can I create a buffer to drive such low impedances?

Take a look at this:
http://www.allaboutcircuits.com/vol_6/chpt_6/10.html

 

Notice you have a 150 ohm resistor on the output when you show the schematic that is clipping. Most op amps cannot handle resistor loads smaller than 600 ohms. Usually a few k ohms is preferred (see Shagas' comment in post #2). You can use an audio amp (like an LM 386n (less than $1 each) if it is a low fidelity project or an LM3886 for a higher fidelity project ($6 each) - each can drive as little as 8 ohms. Alternatively, you can build a transistor driver stage. See TubeGuy's suggestion on post #3 above.

 

The answer is in the datasheet, but it's hard to find.
See the attachments.