Hi, John.  Your product choice leads me to think you're looking for a lower-impact product, and I do have an option for you without the additional salts.
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Chelated iron products are excellent natural broadleaf weed deterrents.   Chelated iron is a micronutrient for turf as well, so overspray and repeated applications onto the lawn will not cause damage.

Creeping Charlie is hard to control because of its aggressive underground rhizomes.  Although fall is typically the best time for treatment,  at this point, waiting until spring is a good option for you.

Any product, synthetic or natural, will require repeated applications.  In the spring,  as soon as the plant starts greening up and growing,  follow the directions on the label for initial and follow-up applications  (typically every two weeks)  until you've reached the level of control you want .  Don't treat in the heat of summer if you have stragglers. Restart treatment, if necessary, in late August. 

To retain your border over time, spray only the specific plants you wish to remove, but remember that the border plants will assertively try to reach back into your yard.   Using chelated iron is a natural,  very low impact way to maintain the area.  

Iron will stain clothes and concrete,  so use care where that might be an issue. 

You'll find chelated iron in easy  - ready-ro-spray bottles at most any hardware or garden center.  (Pronounced key-lated, and also may show iron as Fe.)