When you are to invest in a new QCM-system, there are several aspects of the instrument to evaluate. Price is often an important factor, and so are experimental capabilities and data quality. Price is straightforward to assess, but how about the other two factors? And how do you compare specifications between different suppliers?
Hardware design and experimental capabilities
The first aspect that comes to mind when assessing the suitability of a specific QCM setup is most likely the hardware capabilities – will you be able to run your planned experiments? For example, if you plan to run experiments at certain temperatures, then the setup must be specified for that temperature range. The experimental capabilities can often be evaluate by looking at the product information, the instrument specification or by asking the supplier.
Data quality and reproducibility
Another aspect that is important to consider, and which is often trickier to assess, is the quality of the data generated. Because what is the point of running the experiments if the results are ambiguous and the QCM data cannot be trusted? Or, if it is not possible to resolve via the measured signal what happens at the surface? Therefore, the parameters related to the data quality and reproducibility are highly relevant to evaluate.
Parameters related to data quality – which are they?
The parameters related to data quality can be challenging to identify. Not only can the terminology vary between suppliers, but different sets of parameters are often used, and theoretical values are frequently mixed with values relevant to the measurement situation.
Therefore, the following should be kept in mind when assessing a QCM specification from a data quality and reproducibility perspective:
Which of the parameters specified impact the data quality?
Which parameters are theoretical, and which are relevant to a measurement situation?
How can the respective specified parameter be compared between suppliers – are the suppliers using the same terminology? A key is to look at and compare, the units that are used in the different specifications.
Under what conditions are the specified numbers valid?
Download our guide on how to read a QCM specification to learn more about which specific parameters that are related to data quality, what they mean and why they are important.
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