[Spm] help on force-distance data analysis

[Vinayaraj OK]

Hello dear SPMers,I need your help on data analysis of forcedistance curves using AFM. I am using Veeco Multimode AFM with version 6.14 software.Considering the photodetector sensitivity calibrated and knowing the spring constant of the cantilever, we could calculate the Force data which is the Yaxis. This is by first multiplying the photodetector voltage value with the photodetector sensitivity (which gives the deflection value 'd' in nm) and then multiplying it with the spring constant.I am confused on the Xaxis. Initially for Xaxis we have the 'height position of the piezoelectric translator'  Z. To get the actual distance between the tip and the surface,is it by adding the Z with d or by substracting?should I consider the signs of any of the values. Because my raw data include both positive and negative values for the Z ?Another question is regarding the post measurement normalisation. I was not using the trigger mode and hence all the curves are not set to Zero force def
 lection line and equal trigger threshold.Is there any easy method (or some software) by which I can normalise the different curves so that I can compare them?Expecting your valuable comments. Thanking you,best regardsRajDear spm! Get Yourself a cool, short @in.com Email ID now!
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